Any crabs? I don't think those fish ate him. If he died from some other cause, the boxer (coral banded shrimp I presume) or hermits, if you have any might have done what they do. I still think he's in there or pieces of him if he didn't make thru the acclimation.
Bet he's under a rock, still afraid of the larger fish that were already there.
I have seen those fish lay on their side an hang underneath a rock, so I would bet that he's still in there.
Try some garlic laced food too. That seems to get everybody in my tank out from their hiding places.