Realize I've only been doing this for about 7 months, but with that said. . .
I've had my anemone (GBTA) make contact with my cabbage leather coral, and it didn't seem to have any particularly ill effects. It's been about 4 months since that first happened. Leathers seem to be pretty hardy. Still, if the leather and anemone are in regular contact, I'd move the coral if you can. It's best to avoid forcefully moving the anemone, so if I were you, and moving the leather's not an option, I'd probably just keep an eye on it, and if it doesn't look like it's being harmed, they're probably OK where they are.