Well that really didn't clear things up much. One sentence they say you can't do it then the next they say you can.
Yes, I had a set of chrome wheels coated but the chrome must be sandblasted to help the powder coat to adhere. HRP
What is the part and are you going to powdercoat it yourself? You need the rough surface for mechanical adhesion.
I run a powdercoating business. I powder over chrome all the time. I black out brand new Harley bikes all day long. The key is having good chrome. I media blast it first with aluminum oxide. Good chrome will stay intact. Bad chrome will peel off. Any chrome with rust, pitting, or peeling needs to come off completely with aggressive blasting.
Its a waterpump pulley and I planned on bead blasting it if that would give it enough bite. And no, I'm not doing it myself other then the blasting.