It might be a bit out there, but is it possible that it's not just his skin that's sensitive? For example, could it be that he's actually got really sensitive hearing or something as well?
The reason I ask is that perhaps he's hearing things while he's asleep that's influencing his dreams and because he's asleep he's not able to process the sounds etc.
I'm just trying to think of other things that could be an issue . Must be so awful to see him going through that .