(Actually there is a chance he is still in Stans mind. Because if he was in Stans mind and was a memory, when he got his memories back with Bill so there is a 50% chance he'll be back. Still don't believe me? Alex Hirsh couldn't say goodbye to Stans memory or Time Baby and Bill was a better character than Time baby if he was strong enough to destroy him but remember See More▼ that was in TIME DODGE so Time Baby couldn't be gone completely so why would he say goodbye to Bill? So Bill could still be in Stans memory live and well, just waiting till he is at the anomalies that Ford was talking about. Or I could be completely wrong. :3)