Boruto Theories

I have been hearing a lot of theories of how Boruto learning Flying Rajin jutsu from his grandfather through Edo Tensei Jutsu. I mean I would love to see more Minto, but I have another theory that I haven't seen around and I honestly think it's realistic. After Minato's death, the jutsu didn't just die with him. It was still being used by the 4th Hokage Guard Platoon. They used it during the Fourth Great Ninja War in episode 523. Granted it needs three shinobis to use the jutsu, but the point is there were shinobis able to use it within the leaf. What do you guys think?