Who Gives A Fish Forums

Palythoa grandis can be picky about flow. What's your current setup? I've had success with moderate flow, not too direct. Also, check for pests like nudibranchs, they're sneaky.

I'd say if you can't put live rock with fish, then you can't put any rock with them - most rock with some porosity will eventually become live. Honestly, find a new LFS, theirs seems a bit off.