Brock would never be allowed in AEW period.
NO ONE would want to work with him because Brock never loses unless it's forced upon him (Cody, Roman) and more to the point, even ignoring the piss fetish shit and him being implicated in Vince's current scandals, Brock's got the whole homophobia shit hanging over his head from his infamous SI interview he did that is just waiting to crash down onto him like a sword of Damocles.
You think the Bucks were cunts before, wait until they have to deal with Brock. The only upside is that Brock will probably legit murder the Bucks, Hangman, Perry, and Omega if they start shit with him.
Their only real option would be for Discovery to force Tony to bring Punk back, force Tony to fire the Bucks, Perry, and Hangman, and basically force Tony into a position of utter castration where Punk is handed the company to do whatever the fuck he wants with it as far as being made head booker and being allowed to fire people as well, to cleanse the company and recreate it in his own image. Nothing short of Punk returning to AEW in triumph will bring people back and stop the anal bleeding and nothing short of Tony being stripped of his company and Punk given what he probably wants most of all at this point in his career, a company to control 100%, would make him leave WWE at this point.