Can you post another video of calling the dog to heel all the way thru to the reward and maybe 10-15 seconds after. And yes the reward should come from the left hand. Guide the dog by holding the leash in the right hand, lure and reward with the left. I made a similar mistake with my pup and even the I held the reward in my left hand I had a habit of holding it near my stomach rather than out front of the dog and we had that same wrap around going on.
But yes he looks great overall. Good focus and he seems happy to be working with you.