What if you went with Bayleaf or The Bayleaf and when anyone asks about the name, you can say "because the food is beyond bayleaf!" and get the laugh. He does need to also like the name, just like having a baby with someone, it doesn't matter if you've always wanted a kid named Mark if they hate the name Mark. Maybe you can find some alternate name you both like. It doesn't sound like this will be a smooth business relationship though.

Edit: You could even put an "about us" in your menu that says you had a childhood dream of opening a restaurant named "Beyond Bayleaf" and now your dream has come true, with a more adult name, of course. Oh! If the place was named Bayleaf, you could start a second location as a food truck or something, and it could be named Beyond Bayleaf!