Anemone crab

[iamstella]

I work for a company that has a large saltwater tank. There are two anemones in the tank right now. A third one died. The one that died had a clown fish and an anemone crab living with it. The clownfish seems to be doing ok, but the crab seems to be missing. It is not living on either of the other two remaining anemones as they have taken residence on the side of the tank. Should I be concerned?
I am the only one who is feeding the tank right now and I've kind of taken ownership of it.
Thanks,
Stella