Had it where a RIO had been damaged and the system had Call Alarm Co on the keypad but would still set with RIo missing and override the remote reset, Galaxy tech came to site as they didn't believe it. Firmware updated all fine.
setting logic as you said, but a better way would be a RKP in each area so 3 RKP and assign them to the area
Dont know how an inspector would interpretate a keypad unsetting an area from outside the area
BTW the communal will have to be area 3 on a galaxy for some reason
Put a LED no resistor across the 485 pair and it should pulse when telemetry commands are sent.
Hard reboot of the camera, you have probably lost all programming and will need setting up again