I would say he is still hungry. I assume the snake is more than a month old and really, hatchlings only eat hoppers for 2-3 meals before moving to small adult mice.
You could try offering another hopper and see where that takes you.
A mouthful of substrate won't hurt him. He will most likely try and spit it out but ingesting some is no big. They can digest bone and hair, a little wood can't hurt.
Reply With Quote