So I'm new to owning snakes but scale rot seems to mostly be on their bellies from substrate being too moist, googled scale rot most pics were belly shots, it looks more like the snake may have been chewed on by a feeder, or somethin in its enclosure scraping on its back maybe the hide entrance? Just guessing someone will have more to say. Don't seem like the snake would need put down, or why he would think that, seems like it would clear up just keep it clean and try to prevent infection.