Hi Isaac,
I am guessing you want to know how to catch your Pseudochromis, right? How much trouble will it be to remove your rock or décor? Do you have a bucket or clean trash can you can put the rocks in, until you can catch him?
You will have to trap him. Place a large net ino the tank and let it sit there for over an hour. Then feed right over the net. When he comes over to eat then catch him. Is he that bad that he realy has to come out? Did you JUST add the other fish? They do accept new arrivas, just nippy at first. I wouldn't get rid of the Psudochromis.