Cibo has great pre-made gluten free sandwiches. My daughter has celiacs and it is very reassuring that they are made in an off site facility and wrapped to protect them. Thanks Cibo! The lady also said they are in other terminals in leguardia as well.
There is a food court market where a Celiac can build a meal from chips, cheese and salads. There are also four places surrounding the area with "gf menus" that consist of lettuce and a tomato. Not a meal and horrible CC. The market is your best shot.