Some people just plain hate the taste of cumin, the way they hate cilantro (not my favorite kind of people, but there's nothing really wrong with them other than stodginess and timidity).
To me, the idea that herbs and spices must be
only savory or
only sweet is hooey. Where would Jean-Georges Vongerichten be now if he had believed that? Not that I like the
idea of a puree of golden raisins and green olives, but maybe it tastes and looks better than I imagine it might. I DO know that black pepper in a cranberry granita or basil in an ice cream are to die for, as is cinnamon with lamb!
Maybe you should try to educate your head cook and production manager. Sure, there are "classic" flavor combinations, but they're not the only possibilities. I do agree, though, that if you're going to try something new and different, do it on a small scale first.