First movement is at 10 seconds, for anyone else analyzing the pitch.
The kid's looking good. Most of the comments may have more to do with development and coordination as he matures. This means he may work a lot of this out on his own with repetition.
His arm is a bit late. He's a fraction of a second early with his hand break. His knee is still moving up when his hands separate.
His elbow is a bit low and front foot strike, but he manages to get it where it needs to for external rotation.
His arm angle is a bit open when he gets into the cocked position when his stride foot is fully down.
His external rotation is a bit abbreviated. I think this is due to opening is front foot for landing which is opening his hips just a fraction early. If he can land with his toes a few degrees closed, it will add torque through the trunk and probably help achieve full external rotation and forearm layback.
I would also try to get him to follow through more since his chest is finishing a bit high.
Overall, a very solid delivery for his age.