Hi LogicallyMinded,
We have had this discussion before, but the argument that CA11 is mentioning is convincing to me. Trump is relaxed and his hand is holding the mic stand shortly before the first shot is taken. He is also smiling. Looking at Doug Mills photo, Trump is already raising his hand and has a frown on his face. Nobody is that fast with reacting to something, for bullet on the photo to be the first one.