I would say that it could be fine and nobody would say a thing or it could be an issue. Really it will just depend on their policies. It's not like you're bringing in McDonald's, it's another restaurant at the CR. However, eating food from another restaurant that your server didn't bring you is bold imo. I totally get kids are picky, mine are picky too but there's no difference between doing that and bringing a meal from home. I was a server in college and even though it doesn't seem like a big deal, it rubs some people the wrong way. I would try to find something on the menu or ask for something that he likes, or find another restaurant that will work for your son.