Hi, Bill. There's a hard rule in marketing. The best marketing in the world can't make up for a deficient product over time. Same thing in music. Your addition to the product offering at this place is maby 20% of the mix (if you consider price, promotion, place, people and all the variences of these).
Generally music at a restaurant is one of the refinements, and cannot be expected to fill the place by itself.
Sounds like you took the high road. I find that most restaurant owners don't know how to choose and promote music very well.
Way to go!
Russ