Im wondering if by leaving it in hot water for so long, you are 'cooking' it a bit and may have a smell or something that is putting your snake off.
I put frozen rats in cool water until thawed and then hot water for about 5 minutes. You could also blast it with the hair dryer for a few seconds, but my snakes dont seem to care so much about temps, so I havent done it.
Sent from my LM-X220 using Tapatalk