I've been wondering this too. It's entirely possible to damage (too mushy or explode) or even cook your prey item when you place it in hot or the hottest your tap water can get off the bat, even if it was thawed in the fridge beforehand.
Anyways, I hope your boy eats for you again Hila! I'm agreeing with Redshepherd and just wait abit longer to give your little one more time to recover.