I agree that it is most likely a flesh wound. Too many people are assuming the deer was standing in a natural and balanced stance that put its spineparallel to the ground when the arrow struck.

We know how a deer can duck on a normal shot, but if this one deflected off a branch, giving that deer an additional split second to react, the deer could have been in any kind of a twisted or turned posture when the arrow stuck. Heck, he could have been sideways in mid air or some variation thereof.

Add on top of that the fact that the arrow was flying erratic after a deflection, we have no way of knowing the actual arrow trajectory.

Could the deer die later of infection? All things are possible, but the deer's activities in the video indicate that he is extremely healthy today. Even if he does,it still doesn't necessarily mean that organs were hit. An infection from a flesh wound is possible as well.

I would not have shot the deer.