Hi.
Generally speaking, fixing a bolt-on neck truss rod is feasible only if the neck is a true vintage/expensive one, or if the truss rod can be replaced without a major surgery.
AFAIK no Fender truss rods fall into the latter category.
A crack in the fret-board (if in the line of the TR) usually means that the TR has came loose or there's a fault in the design/manufacturing.
Pics will help, but usually no-one can give a full answer just based on pics.
On the last thread of this kind I suggested the bolt-on TR repair price for around $400, but that's just me.
Regards
Sam