You are correct. It will only eat molted crayfish. I set up a large aquarium. I then cut up 1.5 and 2 inch pieces of pvc pipe about 4 inches long. I found a bait shop the sells crayfish and bought 5 dozen. I look for molted skins every day. I will either freeze them or feed alive. It will eat f/t. I hope to freeze enough to make it through the winter. I have heard they don't do well thought hibernation in captivity.
Mark