The first thing I would do is be sure he has multiple hides so he never has to decide between security and proper thermoregation. Also, I wouldn’t worry about moving him to a warmer spot. As long as he has a temperature gradient available, he will instinctually go where he needs to go in order digest his dinner. My little scrub python often spends the couple days after a feed in his cool hide instead of basking and he has the fastest metabolism of any serpent I’ve ever seen!
If you’re really worried and he only has one hide right now, you could always just scoot the hide into a warmer spot. He’s still acclimating, so he’ll definitely go wherever you move the hide. Lastly, I would like to discourage you from leaving live prey in your snake’s enclosure unsupervised, especially overnight. I know it was a fuzzy and highly unlikely it could harm your pet physically, but it could definitely stress him out.
in any case, congrats on your new friend and keep us posted!