i think you underestimate how much power the rock has in hollywood these days
and he has a good working relationship with WB and WB is willing to cater to him so he is less inclined to work for the competition or to at least not sour that relationship, he pretty much has a hand in all medias these days from film to tv even sports with xfl - also keep in mind, WB/Zaslav might be super desperate right now too
its not just about making big $$$, its about content and thats where his seven bucks productions becomes very important, they can get content for HBO Max and Discovery too (i think shark week this year was produced by his company)
in the DCEU, his company produced Shazam and Black Adam and the Super Pets cartoons, he is also producing Shazam2 and thats just whats announced so far, wouldnt be surprised if MoS2 is gon be produced by him too
im just saying, its believable as you’re not just dealing with some dudes agency knicking at your door but a whole production company from a guy whose gon’ lead your biggest movie for the year
but who knows, maybe there’s a caveat, if Black Adam bombs then its no deal but the rock flexing his muscle on a company under scrutiny and super desperate… id buy that story