Firefish missing in 5g...should I be concerned?

I got a firefish for my 5 gallon tank, he isn't very big and guy at LFS said he'd do well in my 5g so I bought him. But he doesn't come out to eat and been hiding in the rocks and I've tried everything I can to coax him out without success. So one time I stuck my hand in the tank and he freaked and jumped out of the tank and I rescued him and everything was fine. Today I bought a new coral and stuck it in the tank near his hide-away and I didn't notice he was back there and is no where to be found in the tank. His little hideaway is hard to see completely and get into so I have no idea if he's still alive or he's dead. Checked around the tank and don't see that he jumped out. My hermit crabs and shrimp are hanging out on the rocks and I'd think if he were dead they'd be all over him, right? Should I be concerned about finding and removing him if he's dead even though I have a good clean-up crew? It's a small tank and don't know what a rotting fish might do to my params....help please.