I would try perhaps leaving it in the dark. Does he look interested in it at all? My picky eater will sometimes be interested at first, then seem to loose interest and go back to hide.
For her, I wait until it's been dark in my room (when I'm out at work or it's late night, my lights are off so it stays dark for a couple hours) and then heat it up, wiggle it and see if she takes. I actually got her to strike again with this- she had been only eating if I left it in there before. Sometimes though that's what it takes, leaving it in there, covering the tank back up and lights out again.