He was stopped from fully awakening right away as that would have had catastrophic effects on the local universe of universes. Not quite sure of the details any more, but basically they've delayed the matter a bit but obviously his potentially isn't going to go away any more.
Also... using sapience as the explanation is rather weak in my opinion, there are plenty of ways to argue around that via information theories. Though that does not necessarily totally invalidate your hypothesis, namely that the Chousin might have accidentally created a situation where some one could ascend.