Sounds like a great kid with a lot of promise. Get him a weight lifting
Coach so he doesn’t get hurt lifting some big time weight. He is strong no doubt, but I would hate for him to get hurt. That arched back is really bad. You want a dead lift to be a hip dominant exercise that works the hamstrings and glutes not a exercise that forces tension on the spine and back. Some simple tips that would go a long way Is keep Weight in the Back of the feet with a nice flat back and push that butt back far as you can while hip hinging.