He's so weak and uncoordinated that moving around in the bath wears him out very quickly. I ended up propping up his head to help keep it above water.
While I took the second video, I heard a massive crash upstairs and started giggling. Thanks, Kreature! Silly tegu.
I put Junior back and will head back to church for the last hour. Hopefully, the heat of his tank will help him move his bowels. I'll give him another bath tonight and then, if there's still no poop, he'll head to the vet first thing in the morning for more serious intervention. :(
