Bb seized, can't powder coat?

I want to get my old frame powder coated black but can't remove the bottom bracket.
I've taken it to the local bike shop and they can't get remove it.
What's the beat alternative to powder coating if I can't get it out?

Powder coat it with the BB still in.

If it is the looseball type just clean the cups out with nitromors afterwards or even just wack the bearings in and let the friction wear the paint away.

After a bit of riding service the BB and clean out the gunk.