As in the title, what would happen to Gaul and Transalpine Roman Gaul if the Romans suffer a total defeat at the hands of the Gaulish coalition in Alesia? I assume Caesar and his leadership is either imprisoned or killed in this scenario, so the repercussion of the absence of such figures should also be taken into consideration for Roman internal politics.
Given Gaul was relatively more urban that Germany, is it possible to have some sort of unified country ruling at least over half or a third Gallia Celtica? I imagine the Arverni have a shot at it given their participation in Alesia.