Spoke with vet and this little guy. He may have had acid dumped on him or been set on fire in addition to the other injuries. The vet said he has multiple traumas, some new and some older. He has necrosis of the skin from all his traumas and will likely need surgery. He has been given antibiotics and pain meds, as well as treatment for his other issues such as parasites. He is very anemic (could be from parasites, could from blood loss). He is not out of the woods by any means but he has a good chance of getting through all this and making it to the next chapter of his life where he will loved.