Is Inclement Emerald Switch AI Truly Random?

Context: Doing an Inclement Emerald HC Nuzlocke on 1.8 Challenge Mode, and one of the things that's been kind of bugging me is the game's switch AI.

It sort of screwed me over in Flannery's gym fight, and upon further research, I found a comment by the hack's creator that claims the switch AI's random because the code for it doesn't actually work.

Just wondering if this ends up being true in practice (somehow I haven't lost the run without actually verifying this), or if there is a level of predictability in the game's switch AI.