I could be crazy, but at the 19:50 mark, as he is turning back around, it appears that he is struggling with some substrate that is caught in his mouth/jaw (I think you can see a piece of it sticking out of one side). He appears to be rubbing against the hide in an attempt to dislodge it. I wonder he wouldn't benefit from a larger substrate...like cypress mulch. I use cypress in my tank, and I have never noticed a problem with it sticking to the prey item and/or getting caught in my snakes mouth. Just a thought, based on my observation of the video.
Aaron