I owe him no such thing, nor did I attack him. I spoke of my own state of mind, that his comment made me think he was dishonest; I did not say that he was.

Omitting the truth is just as dishonest as lying. You don't try and parse technicalities with honesty, either you were acting in good faith or you weren't, not telling the restaurant that you intend to sell the reservations - something certainly outside their expectations - is deceptive and is most certainly dishonest.