Put a live rat fuzzy or pup in the opening of his hide and LEAVE. Let him find his food and eat where he feels safe. Make sure there are no distractions.
I did try this also but with a f/t and a prekilled (and a bloody prekilled at that). I left it there overnight with him again. He just pushes it out of the way and then goes to cruisin around I wake up in the morning just to find the rat pushed to the side of the hide a bit.

I will feed live if I have to. I wouldn't let him suffer, trust me I just thought I would go through all the tricks first before I went to live. I just hope that if I give him a live rat pup he eats it. For his sake and mine I had to have the guys at the store kill the rat pups for me. Not easy being a vegetarian snake owner but I'll do what I have to lol