The Moorman photo could not have been taken when Clint Hill was bolting for the limo. That's because it was taken at Z-315, which was two frames after the fatal head shot, and the Clint Hill stuff came later.
Here's the Zapruder film with frame numbers displayed:
Here is Z-315 from the above film, which corresponds to the Moorman photo.
Then I kept watching for Clint Hill:
That's Clint Hill at the back of the limo, but it's a full second later than Z-315, the time of the Moorman photo, and it was probably later than that because we know that they removed frames from the Zapruder film in order to hide the slowing and stopping of the limo.
And when you think about how advanced this is, you realize that Mary Moorman would never have waited that long to take her picture. Remember, she was waiting there, ready and prepared, before the Kennedys reached her. Why would she let them pass by only to shoot them from behind? Who would do that?
Look at this Nix frame that Robin Unger put up to represent the time of the Moorman photo.
He's arguing that even though she was there, poised and ready the whole time, Mary saw the limo approaching from her right, let it get to her and then let it pass her only to take her picture at the angle you see below. Who in her right mind would do such a thing?
Obviously, she took her picture before that, as any sane person would. And if you look closely, you can see that she didn't even have her camera raised to her eye at the time. Of course she didn't because she had already taken her picture. This was well after the Moorman photo.