A multiverse is something external to any one universe in that multiverse, so even in an infinite number of universes there cannot be one which redefines what’s outside that universe.
The way it was stated is not a paradox, it’s simply logically invalid.
Valid statements would be that in a multiverse there can be one universe where it’s impossible to access the rest of the multiverse or that there can be one universe were the theory of the multiverse was never and will never be thought of.
And then of course, on top of this there is @Carnelian’s even bigger point, which is that it’s perfectly possible to have an infinity of possibilities which are all bound by certain rules. A simple mathematical example: there is an infinite number of decimal numbers in between the integers 0 and 1.