My point being that replacing the head didn't cause the demise of the rod bearing.

Rod bearings don't usually go suddenly without any warning, so if it wasn't noticeable before the repair, it was damaged during your short drive, which is usually the result of detonation, which is usually a tuning issue. Just saying.

He doesn't want to rebuild the engine just for the fun of it. I can't say that I blame him. If the short block is in reasonable shape, it could last many years given the average number of miles these cars get driven.