Do you honestly think tons of employers are going to sit their employees down and have them watch a PSA? Employers who think it there is enough risk probably already have in house plans, like every hospital I've been in.
And when do you think they will be showing it in school? Health class? What age group is actually going to benefit from it? And again, if the school thinks there is enough of a risk, they probably have their own plan in place.
And as I said before, a 30 second TV commercial is useless. That is enough time to tell people the basic run, hide, fight, to which they will they will all say "no freaking duh".
So great, it is on the internet. So are about 100,000,000 cat videos. Being on the internet means some people will see it, but it doesn't ensure wide spread distribution. The people who see it have to actively seek it out, and many of those are going to be people who already have some idea of what an active shooter situation is and are probably not going to learn anything new.
In short, I am saying it was a waste of money for a PSA that will have a limited audience and advocates doing what the vast majority of people would do anyway.