He was misted quite a bit that day (maybe about 5 times, normally is about 3 times) as I was advised this helps them along with the shed, could this have caused the wrinkling?
I have just read that it can be normal for skin to wrinkle when they're about to shed.
Either that or he's severely dehydrated..but his urates are completely white and has shown no signs of dehydration (something I am always on the look out for) and he was mid shed and he bounced back to normal the moment he was done shedding.