[higgmeister]

Can’t believe the dude in the hat just stands there for much of it while everyone is ducking.

Those two guys were plain clothes Secret Service and were scanning the crowd trying to spot the shooter.

[RummyChick]

That guy does not look like Secret Service. Black hat. Stubble on face. right behind trump

[Steven Tyler]

Dunno.
The President was looking at the screen to his left.
Therefore, shot came from the left or from the crowd behind (???) him