The video is a little cut-and-paste and somewhat confusing. From what I have gathered, the first scene you see is the two robbers holding a cashier at gunpoint. The owner of the establishment sees this happening on surveillance and steps out from a door across the drive-through area (this is where the video cuts to another angle) and he calls out the perps, drawing their attention toward him. One runs at and shoots toward him as he engages and hits the guy multiple times. This was a bit crazy. Training is hugely important for things like this. Things are fluid and crazy and you have to be able to make good hits. Notice he is making good hits and the guy still has the ability to run up to and past him and fire shots. Moving isn't a bad idea, but getting hits is a better idea. Both is optimum, but you do what you can and this guy did a pretty good job. When the trainer tells you "shoot until the threat stops," this is what is meant. This threat never really stopped until the guy was running off.
Here is a clip of just the store video. It is confusing without a little explanation of the situation from the above story, but it's easier than watching all of the blah, blah, blah in that one.