The first picture shows a guy coming out of the building...looking down...oblivious to everything....seems out of place...wonder which way he went
Do you mean the guy in the gray/white jacket with what looks like a bag over his shoulder? Up to the right? I noticed him, too. He’s not watching the race, but looking down.
He looks Asian, but I don’t want to speculate. Maybe he was the first in the building after the explosion due to a stampede of people.