Have you seen the tape about the wardrobe change??
http://www.youtube.com/watch?v=bYc7o_wQ6wM
On the original helicopter footage the yellow shirt guy is at the beginning and the second guy is at the end.
One possible explanation for the behavior of the Yellow Shirt guy is that there was an incident involving a camera man that went on for some time.
Yellow shirt dude may have just been hanging around to see what happened.
Nope .. yellow shirt is shorter, skinny: black vest is bigger, fuller