Update:

it’s been quite a long time since the last time I tried feeding him. Yesterday morning he was out of his rock (very unusual) and just sitting there motionless. He hissed at me when I looked at him and was in strike position. I thought for sure this would be the day he would eat so that evening I went to get a rat and he didn’t eat it. He stuck his head out and got close to it and then he hid again. I tried reheating it multiple times in hot water and still nothing