Quite possibly he was only superficially wounded. It hurts like hell to get shot no matter what type of round it is and it will carry fabric from the clothing into the wound with it increasing the odds of infection.
Odds are the shooter was using cheap hard-ball ammo or full metal jacket that wouldn’t expand but pass right through. Still, it would have taken me off my feet for a couple of days, especially it hit something important, like say an artery.
It could also have been a ricochet, or the bullet could have passed thru something else before getting to him. If he moves around as much as this guy did, it wasn’t a very solid hit from ANY bullet. Anyone who doubts that can come by and let me shoot them in the knee with my 22 revolver...