Veggie risotto (use vegetable broth instead of chicken broth)

Curried vegetables over rice (you can grill some meat and have it on the side for the non-vegetarians)

If you have access to corn tortillas, you could make bean & veggie enchiladas or soft tacos.

Bean and vegetable chili (use vegetable broth, not beef broth)

Hearty vegetable soup with salad and sandwiches available for those who can eat bread. (Gluten free dressing can be made with lemon or lime juice & olive oil)

Cabbage rolls filled with rice and beans or sauteed veggies – cover with tomato sauce to cook

Stewed veggies/beans over polenta (corn meal)

As for desserts, anything with fruit is perfect. Fresh fruit sorbet, fruit topped with yogurt and nuts, etc…
There are also some gluten free pie crust recipes you can find online — they’re often made with nuts but I don’t know the recipes offhand.

There are many gluten-free web sites so you may want to check some of those sites out for recipes and then choose the ones that don’t incorporate meat. Although, you should make some meat available for the remainder of your guests that are meat-eaters. They’ll appreciate it.

You’ve got quite a challenge… Good luck & happy cooking!!