A warm side temp of 91*F is too high, drop it down to 86*F. Any higher can cause neurological issues.
The minimum humidity for a baby is 90%, go ahead and let the substrate be wet. I used cypress mulch for my babies when I bred my female a few years back; the neonates spent all of their time burrowed in it, and cypress doesn't have mold issues.
I would also remove the wooden log hide, it will mold quickly. With a BRB plastic hides are your friend. If you put down an inch of substrate I wouldn't worry about adding true "hides" as your baby will burrow, just put in some fake plants to simulate ground cover.