No worries at all--some people allergic to mint are allergic to mint, full stop. There's no reason to expect that it'd extend to rosemary, oregano, basil, thyme, lavender, marjoram, and even the distant perilla/shiso cousins. grr. I have become a cautious fan of ground coriander and cumin seeds for pan-frying pork.

Yep, we eat some nuts, though mostly assertive ones that wouldn't suit tagine. At least, I have trouble imagining tagine with walnut or pistachio. Other things along that flavor axis with those things (baklava!), but not tagine. Maybe cashew.