I'm sorry, I know it's really not funny, but I laughed so hard at this because I've literally done the same thing with my old cleaner shrimp, lol. It always tried stealing from my elegance coral, but even MORE annoying - he would grab food from my long tentacle anemone, right out of it's mouth. That nem was huge, the shrimp is lucky HE didn't get eaten.
I guess I just was lucky that once I started giving the shrimp a big chunk of food before spot feeding the corals, he'd chow down on that and mostly leave them alone. That shrimp has long since passed away, but I still have a large fire shrimp. Interesting, the skunk cleaners are SO bold, but the fire shrimp has always been super shy. He never ventures more than a couple inches away from his cave. I actually feed him a big piece of mysis every other day with long tweezers, so I don't scare him - otherwise he won't come out to grab other food. I'm sure I have the most spoiled shrimp ever, lol.
I don't really have an ideas for you with yours, other than possibly setting one of those mushroom cages on top of the scoly when feeding, to keep the shrimp out?