I read in a GREAT BIG BOOK OF REPTILES that some Galapagos giant tortoise's are called saddlebacked because their shells look like saddles and the look like that because they need to reach up to grab plants off high plants with their necks so their shells look like that so they can reach high with their necks so maybe it's fine!
Your friend should get his dna taken he might have some lonesome george genes. That would be awesome if this was lonesome george 2. Never know especially how old he is if he really is around 100. Could be another chance for that species.