Hi Greg,
You should give RadioSync a try.
Besides other things, it serves as a kind of "converter" between TCI and CAT, or VAC.
You can create your own virtual COM ports and audio endpoints.
You will find RadioSync.exe in the ExpertSDR program folder. (normally C:\Program Files\ExpertElectronics\ExpertSDR3)
Best 73
Eberhard, DK8JV