Don't think they are fire damages the bloke brought them to refurb but never got around to it
They really look fire damaged to me, so you need to find out 100% for safeties sake! consider that the wheels may have received thermal shock, if the car they were on was on fire, wheels could have got hot well beyond normal temps, and the Fire Brigade may have doused them with stone cold water... not good!
The other thing that may make them look like that, is that they have been chemically dipped, and not cleaned after, this could again lead to problems with refinishing if acid residue is trapped in the pores...
If this is the case, I would advise media blasting, then powder-coat.
Thom