He’ll be stop way before he ends everything.
Don’t forget, the main reason he got so far was because prior to attacking, he was already feeding of the Anti Matter verse, an infinite multiverse that belonged to him. Does Marvel possesses such a thing for him to feed on?
Also, Anti also fed on the positive verse, and he was being powered by two infinite multiverse.
He gets far and might even succeed if he’s able to feed on the anti matter in Marvel. If it works the same as it does on DC.