Look at the backgrounds from the event. One guy being interviewed had a cloudy background. It was daylight when the fake shooting happened. Oh, and it was at 3:22 pm PST (my timezone), which tells me it was a Skull and Bones ritual.

I found another video where one of Trump's staff was bringing a couple of photographers to take a picture of him while they lowered the flag. It was fake.

Also, the Donald was confirmed to have used Crowds on Demand, which is a crowd renting service. They didn't get hit with brains and blood, and just sat there as if nothing happened.