They have no idea what's in their sushi and couldn't be bothered to find out.
Pre-made sushi has wheat for 3 different reasons: 1) soy sauce packet
2) flour to bind rice
3) soy sauce or mayo in sauces
Neither the floor associate nor the customer service desk knew and when I asked they said, "I doubt labels would help because we use flour to prepare many of our foods and so nothing can be certified"