If the humidity is too high before my BP is blue sometimes he gets restless like yours is in the photo from your first post. I usually keep the humidity at around 60-70% until I see my BP's eyes turn cloudy - then I put sphagnum moss in his hide and increase the humidity to 70-80% and he has a perfect shed each time.
I've found he'll only tolerate the high level of humidity after his eyes turn blue - I've tried putting sphagnum moss in sooner and he will actually push it out of the hide!
Also just to confirm, the lava rock is just a rock that came from hardened lava and it's not an electric/heated rock or anything like that, right? Heated rocks are very dangerous for BPs so I just wanted to be sure.