Well... I don't have much experience regarding such an issue. Assuming the compound has gone down to bare metal or real deep into the primer, I guess you can apply paint in two or three layers with a cotton swab, let it stay there for a few days and then even it out with an abrasive.
I have done this to cure paint thinning over pillar edges on an old car, and it worked. But in your case the surface is flat and the cause is excessive use of an abrasive, so not sure.