Welp, another lesson learned. The humidity levels dipped into the 30's so I broke out the moss (was originally going to wait until the setup needed to be cleaned but the sudden onset of chilly, dry weather forced my hand), and just like with the coconut fiber I needed only half of what I prepared and so I set the rest out the dry so I can store it for later. Also put in a humidity box with more moss to see if he'll use it.

He doesn't seem to like the moss all that much though. I mixed it into the substrate and he's kinda haphazardly staying halfway inside his hide of choice unlike how he's normally fully inside during the day. I'll leave things be for now but if it stresses him out too much I'll clear some of it out.

That said I'm getting worried about what I'm going to do when he goes into shed. Despite all my efforts the humidity's still reading out at 40-50% 24 hours after adding the moss. Lower than the recommended 60% (but still acceptable) and a far cry from the 80% required for a good shed. I guess I either have to hope he figures out the humidity box when the time comes or I have to spray the enclosure like crazy (the CHE saps moisture very quickly) when he goes blue.