I got a large naso from Les too if that is who you got your triggers from. It took that guy 2 weeks to start eating. He was fat when he came in and by the time he started eating, he was nearly bones but now he is fattening up again. They come straight from the ocean without anytime in captivity to learn to take prep foods. He took a couple of nibbles of mysis on day 12 and everyday after that, he started eating more and more. It just takes time I guess since they have no previous history with people and being in captivity. Just have to be patient and provide them with food throughout the day. Eventually when they get hungry enough, they should start eating.
Good luck with those guys. They look amazing!