First, those that are criticizing the shot, shot placement, bullet choice or anything else are opening the hunting community to more posturing by the anti's. Stop feeding them tools for propaganda.
Second, you have no right to criticize until you walk a mile in that mans shoes.
Third, we can not tell what the first shot did. The bull arched his back and clearly stood still not knowing what happened. One shot, one kill clearly does not happen every time. Perhaps it was a heart lung shot and the bull would have gone down anyway. It's non of your GD business.
Having only watched on video, I can not say one way or another how good the shot was but recent videos I have seen with really big guns and bullets still do not drop the animal first shot, even when it is clearly a heart+lung hit.
IMHO only those who feel they have flubbed a first shot get to criticize. Everyone else is a DH.
I have flubbed PLENTY of shots starting with my first deer at 14 when I gut shot it and it hunched it's back just like this elk. So I must not be a DH (whatever that stands for) and have the right to criticize. Sure, we'd all love to pull the trigger once and the animal drop like a rock but as you said, they don't always drop right away.
My main complaint with this particular video is that A) The decision was made to stall putting more rounds in the animal which to me, is inhumane. and B) They decided to post the video which is a HUGE tool for the anti's.
I think the simple fact that we are discussing what could have been done differently, offering each other our experiences, and sharing our knowledge to prevent inhumane kills is a bigger defense than saying it's none of your GD business! By publicly posting this video it makes it our business.