+2 on dipping it. Hard to tell from pic, but don't see what I recognize as brown jelly, but dip it to be sure. Also, how long have u had the coral? Short term could b shipping damage common w/ torch.
I've witnessed 1 of my emeralds scraping its claws across a goniopora frag. Thought it was doomed, but moved it and crabby seems to have left it alone. If you've had the coral for a while and it has been fine, I always look for the lowest common denominator...what changed recently...adding crabs, water parameters, water flow change, did something fall against it. Might come back after dip if there is no brown jelly.