In addition to the duct tape and gauze squares, if straw is out for allergy reasons (I had a hunter who broke out in hives horribly on straw, and some straw makes me itchy too, which is why I mention that, not saying this is your situation) could you try paper bedding mixed in with the shavings or the pelleted bedding wetted down and see if that’s softer for him?
My colt had his foal wellness check yesterday and got a clean bill of health from the vet. He needed an extra enema on Monday but perked right up after that and seems to be doing great. He is absolutely enormous and seems so much bigger than my colt from last year but that colt was born 9 days earlier. It’ll be so interesting to see where they all end up size wise in a few years.