You are right - inasmuch as the real question are: why has Müller made this statement at all? And why now?
As for your point about "putting the Pope on the spot" - the Pharisees used to try to do this too, with Our Lord. He had the right way of dealing with such approach. Namely, either to ignore the Pharisees; or to ask another question of them, in the hope of making them think.