He doesn't actually know. But now that the initial shock is wearing away, he's pretty sure he can weather this. Daniel knows experiment. If he had more specific information, wouldn't he have led with that?

"My stone's put together differently. It stores more energy than anybody's but maybe Pride." Energy here meaning screaming ghosts. "I don't know if it was so I could shapeshift or if I can shapeshift because Father needed to store some excess." All true. All mostly meaningless.