Vendor Names Changed On Save Without Any Reason

SOLVED

This issue may or not be related to the Vendor.IsModified always being true (https://www.sagecity.com/support_communities/sage50_accounting_us/f/sage-50-u-s-software-development-kit-sdk/132513/vendor-ismodified-is-always-true).  I'm posting it separately in case it's not.

The problem I'm running into is that I can load a Vendor, change absolutely nothing in it, then call .Save(), and the name is changed only when writing checks to the Vendor.  For testing, I'm using the same code that's in the question above.  I load a Vendor, which has the name "Housing Authority of Champaign County".  Without changing anything, I call .Save().  Now at this point it appears nothing on the Vendor record has changed.  I can close my app and re-open the record, and the properties are still the same.  I can find absolutely no evidence that anything has changed.

However, if I now log into Sage and go to Tasks -> Purchases/Receive Inventory, then select that Vendor, the name appears as "Housing A. County".  I have attached a screenshot.  Also, after loading the Vendor record into my app above, I used JSON.Net to serialize the Vendor so that I could review all the properties in detail; I have attached that as well.

At this point, please try to reproduce the problem.  Everything below is just follow-up information that might help find the source of the problem.

We discovered that after seeing the above issue, they could open the vendor record, change one letter in the name, Save, then go back to Purchases/Receive Inventory, select the Vendor again, and the name would appear correctly.

So I tried doing the same thing in code.  Where I previously just had .Save();, I put the following code:

var oldName = vendor.Name;
vendor.Name = "";
vendor.Save();
 
vendor.Name = oldName;
vendor.Save();

Amazingly, this caused the name to get saved correctly with no side-effects.  I tried many, many variations and alternatives, and I couldn't find a solution other than this workaround.  The code above is the exact workaround I had to put into our production code to solve the problem.

Please advise.  I can't imagine that a bug as bad as this made it into production, but if I'm doing something wrong, I can't find it.  We are running Sage 50 2019.1 and connecting to it with the .NET Framework 4.7.2 from a console app.  I've put in a request to IT to upgrade Sage to 2019.2 to see if it will fix the issue, but that is going to take a while.

(( The JSON file won't upload, so I'm pasting the contents here. ))

{
   "Key":{
      "Guid":"ffec3e3d-62a1-4e92-bd7d-aa74b6346594"
   },
   "AccountNumber":"",
   "Balance":13.0000000000000000000,
   "Category":"",
   "Email":"",
   "ID":"Champaign",
   "IncludePurchaseRepresentativeOnEmailedForms":false,
   "IsInactive":false,
   "LastInvoiceAmount":13.0000000000000000000,
   "LastInvoiceDate":"2019-06-08T00:00:00",
   "LastPaymentAmount":11.0000000000000000000,
   "LastPaymentDate":"2019-06-01T00:00:00",
   "Name":"Housing Authority of Champaign County",
   "PaymentMethod":"Check",
   "ReplaceInventoryItemIDWithPartNumber":false,
   "ReplaceInventoryItemIDWithUPC":false,
   "ShipVia":"Airborne",
   "TaxIDNumber":"37-6000507",
   "Form1099Type":0,
   "UseEmailToDeliverForms":false,
   "UsingPaymentDefaults":true,
   "VendorSince":"2019-06-07T00:00:00",
   "WebSiteURL":"",
   "Contacts":[
      {
         "PhoneNumbers":[
            {
               "Number":"(217) 378-7100",
               "Key":1
            },
            {
               "Number":"",
               "Key":2
            },
            {
               "Number":"(217) 378-7113",
               "Key":3
            }
         ],
         "Address":{
            "Address1":"2008 N. Market Street",
            "Address2":"",
            "City":"Champaign",
            "Country":"",
            "SalesTaxCode":"",
            "State":"IL",
            "Zip":"61822",
            "IsModified":false,
            "IsUnchanged":true
         },
         "Key":{
            "Guid":"d5659bfc-1712-4fb2-a88f-49f956c94f17"
         },
         "CompanyName":"Housing Authority of Champaign County",
         "Email":null,
         "FirstName":null,
         "Gender":0,
         "IsPrimaryContact":true,
         "LastName":null,
         "MiddleInitial":null,
         "Name":"",
         "NameToUseOnForms":1,
         "Notes":"",
         "Prefix":"",
         "Suffix":"",
         "Title":"",
         "LastSavedAt":"2019-09-11T14:46:15",
         "Revision":{
            "RevisionNumber":29
         },
         "IsAdded":false,
         "IsDeleted":false,
         "IsModified":false,
         "IsUnchanged":true
      }
   ],
   "ExpenseAccountReference":{
      "Guid":"986419ad-960c-4554-a185-02ddaed6dd28"
   },
   "Terms":{
      "DueDays":30,
      "DiscountDays":0,
      "DiscountPercent":0.0000000000000000000,
      "CreditLimit":2500.0000000000000000000,
      "ChargeInterest":false,
      "IsStandardTerms":false,
      "PaymentTimeFrame":2,
      "UseDiscounts":false
   },
   "PurchaseRepresentativeReference":{
      "Guid":"00000000-0000-0000-0000-000000000000"
   },
   "LastSavedAt":"2019-09-11T14:46:15",
   "IsSaveAllowed":true,
   "IsDeleteAllowed":true,
   "PhoneNumbers":[
      {
         "Number":"(217) 378-7100",
         "Key":1
      },
      {
         "Number":"",
         "Key":2
      },
      {
         "Number":"(217) 378-7113",
         "Key":3
      }
   ],
   "CustomFieldValues":[
      {
         "Value":"",
         "Key":"Office Manager"
      },
      {
         "Value":"",
         "Key":"Account Rep"
      },
      {
         "Value":"",
         "Key":"Special Note"
      },
      {
         "Value":"",
         "Key":"Federal ID Numbr"
      }
   ],
   "MailToContact":{
      "PhoneNumbers":[
         {
            "Number":"(217) 378-7100",
            "Key":1
         },
         {
            "Number":"",
            "Key":2
         },
         {
            "Number":"(217) 378-7113",
            "Key":3
         }
      ],
      "Address":{
         "Address1":"2008 N. Market Street",
         "Address2":"",
         "City":"Champaign",
         "Country":"",
         "SalesTaxCode":"",
         "State":"IL",
         "Zip":"61822",
         "IsModified":false,
         "IsUnchanged":true
      },
      "Key":{
         "Guid":"d5659bfc-1712-4fb2-a88f-49f956c94f17"
      },
      "CompanyName":"Housing Authority of Champaign County",
      "Email":null,
      "FirstName":null,
      "Gender":0,
      "IsPrimaryContact":true,
      "LastName":null,
      "MiddleInitial":null,
      "Name":"",
      "NameToUseOnForms":1,
      "Notes":"",
      "Prefix":"",
      "Suffix":"",
      "Title":"",
      "LastSavedAt":"2019-09-11T14:46:15",
      "Revision":{
         "RevisionNumber":29
      },
      "IsAdded":false,
      "IsDeleted":false,
      "IsModified":false,
      "IsUnchanged":true
   },
   "PaymentsContact":{
      "PhoneNumbers":[
         {
            "Number":"(217) 378-7100",
            "Key":1
         },
         {
            "Number":"",
            "Key":2
         },
         {
            "Number":"(217) 378-7113",
            "Key":3
         }
      ],
      "Address":{
         "Address1":"2008 N. Market Street",
         "Address2":"",
         "City":"Champaign",
         "Country":"",
         "SalesTaxCode":"",
         "State":"IL",
         "Zip":"61822",
         "IsModified":false,
         "IsUnchanged":true
      },
      "Key":{
         "Guid":"d5659bfc-1712-4fb2-a88f-49f956c94f17"
      },
      "CompanyName":"Housing Authority of Champaign County",
      "Email":null,
      "FirstName":null,
      "Gender":0,
      "IsPrimaryContact":true,
      "LastName":null,
      "MiddleInitial":null,
      "Name":"",
      "NameToUseOnForms":1,
      "Notes":"",
      "Prefix":"",
      "Suffix":"",
      "Title":"",
      "LastSavedAt":"2019-09-11T14:46:15",
      "Revision":{
         "RevisionNumber":29
      },
      "IsAdded":false,
      "IsDeleted":false,
      "IsModified":false,
      "IsUnchanged":true
   },
   "PurchaseOrdersContact":{
      "PhoneNumbers":[
         {
            "Number":"(217) 378-7100",
            "Key":1
         },
         {
            "Number":"",
            "Key":2
         },
         {
            "Number":"(217) 378-7113",
            "Key":3
         }
      ],
      "Address":{
         "Address1":"2008 N. Market Street",
         "Address2":"",
         "City":"Champaign",
         "Country":"",
         "SalesTaxCode":"",
         "State":"IL",
         "Zip":"61822",
         "IsModified":false,
         "IsUnchanged":true
      },
      "Key":{
         "Guid":"d5659bfc-1712-4fb2-a88f-49f956c94f17"
      },
      "CompanyName":"Housing Authority of Champaign County",
      "Email":null,
      "FirstName":null,
      "Gender":0,
      "IsPrimaryContact":true,
      "LastName":null,
      "MiddleInitial":null,
      "Name":"",
      "NameToUseOnForms":1,
      "Notes":"",
      "Prefix":"",
      "Suffix":"",
      "Title":"",
      "LastSavedAt":"2019-09-11T14:46:15",
      "Revision":{
         "RevisionNumber":29
      },
      "IsAdded":false,
      "IsDeleted":false,
      "IsModified":false,
      "IsUnchanged":true
   },
   "ShipmentsContact":{
      "PhoneNumbers":[
         {
            "Number":"(217) 378-7100",
            "Key":1
         },
         {
            "Number":"",
            "Key":2
         },
         {
            "Number":"(217) 378-7113",
            "Key":3
         }
      ],
      "Address":{
         "Address1":"2008 N. Market Street",
         "Address2":"",
         "City":"Champaign",
         "Country":"",
         "SalesTaxCode":"",
         "State":"IL",
         "Zip":"61822",
         "IsModified":false,
         "IsUnchanged":true
      },
      "Key":{
         "Guid":"d5659bfc-1712-4fb2-a88f-49f956c94f17"
      },
      "CompanyName":"Housing Authority of Champaign County",
      "Email":null,
      "FirstName":null,
      "Gender":0,
      "IsPrimaryContact":true,
      "LastName":null,
      "MiddleInitial":null,
      "Name":"",
      "NameToUseOnForms":1,
      "Notes":"",
      "Prefix":"",
      "Suffix":"",
      "Title":"",
      "LastSavedAt":"2019-09-11T14:46:15",
      "Revision":{
         "RevisionNumber":29
      },
      "IsAdded":false,
      "IsDeleted":false,
      "IsModified":false,
      "IsUnchanged":true
   },
   "CashAccountReference":{
      "Guid":"889a65ed-a19e-4fa2-989d-6d18a9f9500d"
   },
   "Revision":{
      "RevisionNumber":42
   },
   "IsAdded":false,
   "IsDeleted":false,
   "IsModified":false,
   "IsUnchanged":true
}