We did this in 2013 with the help of Orchid, who wrote an EFT spec for Global VCard. The client would process a batch as if it were EFT, and select the Global VCard spec when creating the EFT file.  That file would be sent to CSI/Global VCard to process payments.  Pretty painless.  You can mark which vendors accept credit card payments with a vendor group, or payment code or other designator.

Thanks for sharing!