Forgive me, maybe I am too naive, but I do not think that this was a pre-planned sabotage action against you. Honey-mustard coated chicken a very polpular recipe, it is made with a very small amount of honey/mustard (as Potatofree mentioned, if you did not noticed, it could not be so much), porbably with less carb than the cheese has. I do not think they intentionaly left the honey out from the list of ingredients. I have a feeling, that when they made the dish they did not realized that honey is sugar...

Of course I do not know your relationship with your relatives. I have high carbs relatives, some of them accept my choices, some of them not. I very simply avoid to eat with those who do not respect my preferences. Yes, first they felt insulted, when I refused a dinner invitation, but then they accepted it, and we have had great time together since.
My recommendation: next time surprise them with your own dish:-))