If he were a Protestant then he would have a leg to stand on. He's a Roman Catholic and for him and other Catholics there is MORE than sola scriptura and he knows that. He is therefore using FALSE reasoning.
He might THINK he trumped it but he will go down badly...doubled and redoubled!
I doubt any Orthodox Church would WANT the dissident. Who needs it?
Maybe Father Schueller has an old-time girlfriend who is, um, pressuring him.