The photo in question is likely a photoshopped composite. The mysterious hand is a clue, but the lighting is inconsistent. The Dunham’s are overexposed, but young Barry in the middle of the shot is not.
Reminds me of some of the pictures of Lee Harvey Oswald our press produced after the assassination...that seemed to show him in communist poses.
To this day I believe Oswald is pictured in FRONT of the TSBD watching JFK ride by...a few seconds before the shooting begins. Not Billy Lovelady at all. Look at the clothes Oswald was wearing when arrested and compare with the famous picture.
Pictures are easy to “fix”.
But his hand is 'overexposed'.