In addition to the other suggestions, I'd try lowering the temps in the enclosure as well. (Might be tricky if you have it in a rack system...but slightly cooler temps won't hurt the other snakes either) Keep the cool side at 78-80 and the warm side at 85-87.

I'm only thinking out loud, so to speak, but if his neurological issues were caused by a heat spike at some point in his young life, maybe it made him more sensitive to heat in general?

The crumpled paper is also an excellent idea for helping a nervous BP to feel a bit more secure.