Of course Uninstalling/Reinstalling GSX won't change anything about how the jetway behaves when using the Fenix, which is only controlled through the EFB setting.
GSX NEVER operates the jetway automatically, it will do it only in these two cases:
- When you call Boarding or Deboardin
- When you call "Operate Jetways".
Clearly, if you have the Fenix calling GSX Boarding or Deboaring by its own (replacing "you"), the automatic Jetway function in the Fenix EFB should be disabled, otherwise a double trigger might possibly happen if they tried to do the same thing.