@cactusflyer
Since TG compiles all the airlines into just one traffic file, one way of disabling specific carriers in TG would be to edit the line title= .... in the relevant aircraft.cfg.
Eg: In drive where you installed TG Simobjects:\TrafficGlobal\TrafficGlobalFleet\JFAI_737_900\aircraft.cfg
[default location: C:\Users\ your username \Documents\TrafficGlobal\TrafficGlobalFleeet]
[fltsim.1]
title=JFAI_737_900_AlaskaAirlines edit this line to:
title=JFAI_737_900_AlaskaAirlines_OFF
sim=TrafficGlobal
model=
panel=x
sound=
texture=AlaskaAirlines
atc_id=B737
atc_flight_number=
atc_airline=ALASKA
atc_parking_codes=ASA
atc_parking_types=GATE,RAMP
ui_manufacturer=Boeing
ui_type=B739
ui_variation=Alaska Airlines
description=AI
ui_typerole=Traffic Global AI
ui_createdby=Just Flight
that particular repaint will then not be loaded into the sim and therefore will not conflict with AIG ai.
Another way would be to do a search in the TG SImobjects directory for the airline. E.g: 'Alaska' to pick up any texture folders and rename them, for instance, 'AlaskaOFF'.
In most cases, TG has just the one repaint for a carrier and, as you point out, limited aircraft type coverage within each airline's fleet so there shouldn't be that much work involved.
(NB: I doubt this method would cause any problems when compiling TG, but it might be worth testing first, then it's easy enough to reverse if there's a problem. Also, I'm afraid that any changes would be overwritten every time there's an update to TG, but that's not too bad if there's only a few changes to redo)