Im playing a Pontus campaign and I am in the late game by now. I had Pontic secessionists seceede from me, having taken all their cities and destroyed all their armies only their fleet remains. However when I defeat it in battle the game instantly crashes.

I tried to revert back to an earlier save and destroy the fleet and leave only one of their armies remaining however the issue persists and when killing the army it crashes my game.

Obviously my suspicion here is that the event triggered after the end of the civil war is causing the crash. I am only playing with DEI part 1, 2 and 3 as well as faster battle submod.