Yes, he's in very bad shape. I gave him a saline injection and have him in a special 10 gallon sick tank. It's just going to be a waiting game now to see if he has enough fight left to make it through.
Mango is severely dehydrated and malnourished. It could be a genetic problem or it could be from being in a bad environment. At this point, it's hard to say.
Sometimes reptiles fight for so long to survive that when they don't have to fight their bodies just quit. Sometimes their bodies react poorly to nutrition and hydration and they die. It's all a waiting game to see.