It's been a few days since I posted this and I've had a long time to think on it. My issue is less to do with him working on the game, though honestly I would have preferred he didn't, and more about the opaqueness of the PR team about the extent of his involvement in the game.
Just throwing it out there since no one on the dev team seems to want to say one way or the other, it seems that Mike Z is still attached to the Avatar fighting game in some way, at least based on these screenshots I took from their official Discord server