I think people are focusing on the wrong thing entirely.
Getting people to watch the video is ancillary to the main challenge which is to get people to care and take some action.
The video is designed to tug at peoples heart-strings and finishes with the noble claim that "this must be stopped".
What's missing though? Any notion of how it can be stopped and what someone who's just watched it can or is supposed to do.
You're competing for attention with a million and one other advertisers selling products and causes so yes, getting people to even notice your message is a challenge itself. But even if you do get people to view it, you are still competing with those other causes and while shunning is very important to the people who go through it, I don't think the world at large views it with equal importance as many of the other causes vying for their support.
Imagine that the video is played in the middle of the super-bowl. Would it achieve much? I'm not sure that it genuinely would. Focusing on getting people to watch it is not the challenge to focus on IMO.
Also, a new message only has so many chances before people start turning off with "I've seen this before" syndrome.