I thaw rodents in water- cool water first, then very warm (not hot or boiling) briefly to warm them so they're more "lifelike". BUT, water washes off a lot of the rodent's scent- you can pinch-damage the rodent's nose with your tongs to release a little more scent- it may help your snake hit the "target" better, but most BPs need the prey to be very warm- glad you know about using a blow dryer.
Sounds to me like the seller showed you early photos when this snake was a hatchling (with decent body weight) but at 18" long, he's likely a year old, not a hatchling, & it's obvious they didn't update their photo, or you wouldn't have bought him. That's very deceptive, to say the least, & obviously they barely fed him- what some call "maintenance feeding" (just enough to keep the snake alive but not well-fed). I don't agree with this practice at all, & either way, he shouldn't look like this!
I wish you luck- this is an unfortunate way to start off with a new snake. Do keep us posted- we'll help you all that we can.![]()