I'm a person who holds people to what they say they will do and complain if they don't.
So I'd talk to the GM and complain both about the salad course being out of order AND for the manager for not following through on his promise and hit it hard for the latter. This is as much about someone not keeping their word as it was for the out-of-order salad.
Kipper, I would not have left without tracking that manager down and making sure he kept his word.