I am guessing that the long fast your BP did meant that his nutritional reserve was a bit low when he shed. Your humidity was not too high, & if
you notice a snake having a difficult shed, it's good to give them some soak-time in shallow lukewarm water with supervision. Shallow means the
water is NOT deep enough to where he is submerged or swimming...you want about halfway up his widest part, roughly.
I am concerned that after one meal, he is going into shed again: that suggests his body is trying to heal from something. Does he have any injuries?
What about mites???? Look VERY closely on him, in his cage, in his water, on his shed...they are tiny, hard to see, hide under scales (like on the chin)
If he gives you a stool sample (& assuming you find no mites as the issue) I'd take the FRESH stool to a vet to examine it. It must be fresh...
Hognose: how big is this snake? -to be eating an ADULT mouse? If a snake has an overly large meal, they may go into another shed soon...but also,
if one snake has mites or is ill, it's possible the other is also affected. Are their cages near each other? I assume neither is "quarantined" from the
other? And are these your only snakes (or lizards)?