We had the same kind of experience with a broken water/hose fitting to the back of the toilet, in NC. He did come late at night. Didn't have the part went back to his shop, didn't have a hose or fitting, replaced a blown fuse.
Charged us 200.00 the going rate. Said to mention his name the next day, back up the interstate to a small RV Dealer. Their tech who operates as a Mobil Tech had all kinds of parts in his van. Fixed it ten minutes. They didn't know the other guy nor had any dealings with him. Told us what was wrong with our water pump but all he had in stock was thee discount models, we would have to wait two days. One hundred twenty five dollars.
Went on to rally and American coach had the part 149.00 installed for free, which I appreciated with bad back.
Anyway to the chase the Mobil Tech business is very lucrative at 200.00 an hour from time they leave home or shop. So some are getting into it after having limited experience/no experience. You found one. So did we. Nice guy but anyone else would not have charged, however replacing the one fuse and he had done a job and walla 200.00 in his pocket and problems still existed we called him for.