Yes it is temporary but needed you do not want pieces or substrate, bark etc to get in an open wound, you want to keep it clean and free of debri and the best way to achieve that is paper towel.It's a bioactive enclosure, so going to something sterile would mean moving him to a rub... Not sure if this would be appropriate?
Is it digital?I have a humidity sensor right in the middle (put in after taking this photo) it's at ground height and leo spends about half his time under Cork bark and half basking up high so it's possible that it's less humid up high I guess.