There would be protein in the chicken and the cheese, would there not?
My guess is that the OP did exactly what we tell people to do, here on EHell. She figured out the number of people she wanted to invite to her wedding, and then chose food choices that fit her budget. Sounds like she has one main dish with chicken and a second one with cheese, and that should cover the needs/wants of most of her guests.
The larger the number of guests, the harder it is to accommodate every possible dietary plan. Adults with very specific food needs should be able to cope with one meal in their day that doesn't completely meet those needs, either by planning to eat earlier or later, or carrying something with them.
I'm making the assumption that money is tight for this couple, and they are struggling to have a wedding to which they can invite all their loved ones and still offer a comfortable level of hospitality. Yes, their food choices are somewhat limited because of that. But I've been to expensive weddings where the food is plated and every guest gets exactly the same meal--decent sized piece beef or chicken, sometimes in a sauce; 6 one inch cubes of roasted potatoes, and 12 green beans. If you don't like or can't eat the beef or chicken, you just have to hope that you can fill up on the rolls or trade the meat for someone else's green beans.
OP, no matter what you offer for food choices, there will be someone who can't eat all of it, someone else who will complain about your choices, and someone who will take three servings of everything. Once I realized that, I plan events knowing this will happen, and just let the complaints roll off my back. You cannot please all the people, all the time.