You said he's looked like this for 5 months? May be multiple full body stuck sheds. TBH that's one of the worst stuck sheds I've ever seen and he does look a bit skinny and dehydrated, but he should be fine with a good ole dose of TLC :)
Just make sure you make the necessary changes to his enclosure and this shouldn't happen again.
EDIT: my smileys won't work :(