To be quite honest I would be assist feeding him a small f/t (warmed) pinky every 3-4 days. He's super thin and losing him is a definite possibility. I would also move him to a shoe box tub until he is eating and gaining weight. That tank is far too big for him and a smaller enclosure will help him feel secure and eat on his own. But don't put off feeding him any longer. A small pinky every 3-4 days starting today! Feel free to PM me if you have any questions or want to talk more about it.
BTW there is no way a live pinky/hopper could hurt him, they don't have teeth. He's way to small for anything other than a pinky/hopper.
Those hides are also way too big for him. BPs should have to squish themselves a bit to curl up inside a hide. You may have to make your own hide out of a solid colored tupperware dish, small pots-for plants, etc. You will need to cut a doorway in whatever you decide to use.