I am increasingly confident that this is James Bookhout, and I am adding it to our compendium of images of him.
My confidence stems from a process of elimination. That man, whoever he was, was likely law enforcement, considering his proximity to Oswald. And he is obviously very short. Remember that being deep in the picture elevates him in the picture. So, you have to read that into it. And when you do, you realize that he was short, like Bookhout. And there really was no one else- not in the Dallas PD, not in the FBI, and not in the Secret Service- who was short like Bookhout. He was an army of one that way.
But what else can we observe about him? Well, unlike Oswald, he had a very short neck.
Look at the difference. My Good God, Oswald looks like a swan, in comparison.
What about the Garage Shooter? He had a short neck too.
And look how his collar matches Bookhout from next to the elevator.
And again, we are seeing the very short neck on both.
Hey, that's Bookhout, and with a high level of confidence.