While there's always a chance anything will happen in an aquarium, I don't think there's much chance the elegance will eat the clown. If the clown is sick or weak, and if it stays in one place long enough, I suppose it could happen... but in general, I wouldn't be too concerned. There are many other LPS
corals out there with quicker feeding reactions, and I don't hear about those eating fish.
I'd be more concerned about the elegance being irritated by the clown's thrashing and closing up. Sounds like it's doing a little of that already. Hopefully the two will get along better as the days go by. Only time will tell. If it continues, maybe try moving the elegance to a different spot and the clown will leave it alone. My clown killed a bubble coral I had once - didn't matter where I put it in the tank. Sometimes this stuff just happens, just like it does in the wild.