Everyone has opinions and mine is that they should have shot again and perhaps a 4th time to kill the nimal quicker. It is apparent that the spine was hit/clipped and that was what stopped the charge but following that, the buff was alive for a long time. I tghink another shot or two would have significantly hastened the buff's death.

Of course, I wasn't there and this is just my opinion after watching the video.

BTW, excellent shooting. Had the buff not been hit in the spine, the outcome could have been different.