You always have my attention ;-)
About the Autowatch Ghost: I don't know that system, but from their website it does "Immobilisation by communicating with the ECU". I assume that means that they open a diagnostic session to the ECU.
The FIS-Control is programmed to detect other diagnostic devices (like VCDS or the diagnostic tester of the workshop) and will disable itself to prevent conflicts. But if a device is installed that permanently opens diag sessions, the FIS-Control will stay permanently disabled.