I have read that false clowns that are tank raised very rarely host because they have lost the need to. When out in the ocean percs host as a form of protection, but in a tank environment after generations of being in a tank environment they lose that instinct. That is just what I have read.
IME, this holds true, I have only had 2 tank raised percs host, ever, and that was in a carpet anemone I tried getting years ago, stupid, boy did I learn my lesson, and so did my wallet! To steal from GRINS tag, I will never buy an anemone again, I will never buy an anemone again!
Anyways, good luck with idea of them hosting!