There shouldn't be any press fit involved. This fork seems to have threaded replaceable studs (see hex at the base). so the stud is OK, or can be replaced, unless the receiver in the fork is damaged. The issue is keying the spring retaining plate (part with holes) and that calls for checking how the fork and plate were designed.

Odds are that with a bit of analysis the OP can solve this fork related problem. But he'll still have to source the correct (brand specific) stop cam for his brake. Hopefully the maker will come through for him, otherwise he now owns an expensive pair of paperweights.