Personally I would dedicate the tank to him. A fish totally worthy of it, IMO. Have some excellent 'scaping that makes it easy for you to care for him AND shows him off.
It's not uncommon IME for them to remain nocturnal and reclusive in a standard reef or "community" fish tank. Not to mention, your tank isn't really big enough to support a bunch of big fish and big fish are all you'll be able to (dependably) keep with him. Anything that swims or tries to hide in the rock will eventually be fair game....rules out most critters.
I think it makes sense to keep the tank stocked with hermits and snails anyway. Feed him well. If you are going to, have some excellent corals, but remember you probably want the rock work to remain very open to show off the eel to best advantage. I would keep the number down and keep it simple - corals will get broken during maintenance. He may be less shy in a dimmer tank...grow your corals up high to make plenty of shaded areas and to keep the bottom mostly open.
Yeah I would do a minimalistic rock work that sorta looks like a bonsai tree pillars at the bottom and a shelf like structure up top with your corals up top but that didn't answer your question about fish.
With Any eel small fish may become a tasty snack. But maybe a six line wrasse since they like to sleep in the sand at night. Maybe a mandarin since they have toxic skin. I've known people to keep them in a community tank they just kept the eel well fed
Any other suggestions with the eel besides the mandarin and the 6 line wrasse or anything else I should look at to Put in maybe a larger clown I like clowns but they maybe be too small ..... So anymore suggestions would be great
Thanks