(This is still just investigative speculation.)
In the ninth image down in this video image series, Is that the Cowboy hat and hand flag guy on the ground behind the black metal fence adjacent to the two rectangular brown tables with the big black duffel bag?
Then appears cowboy hat and flag in hand guy by the brown wooden picket fence before it was pulled away, in front of the guy with the bone sticking out of his leg on the ground.
How did the cowboy hat hero guy have the presence of mind in all that turmoil to grab his American flag and cowboy hat from his duffel bag before he ran to the help of the minimally bloody legless guy?
Also behind the guy in the red jacket helping the lady up, you see a woman with part of her yellow undershirt showing, spilling the red liquid on the ground behind him.
What kind of clothing do Hollywood directors use that blow off with high pressure air without cutting through the skin? Most of the people who had their cloths blown off had hardly any physical wounds.