The first thing I want to do with the leaf pattern, is show that it just plain can't possibly be a reflection (or part of the background image).
Okay bec, this time I'm going to give you an "A" for awesome! You took the words out of my fingers (computer keyboard), and you even did the red circles so I don't have to! Actually, I like it when others come up with the answers before I do. What you just pointed out is one of the strong points about the pattern—both that it is not a reflection, and also that it (probably) is not Photoshopped into the picture.
Notice especially inside the larger red circle: the pattern stops abruptly at the edge of the paramedic's arm, it does not even fade out gradually—even though the arm at that point is almost as dark as the surrounding background. This indicates strongly that the pattern is actually inside the ambulance, farther away than the paramedic's arm; and his arm blocks the light of that pattern. If it were a reflection, it would certainly continue to be seen at least somewhat on the edge of his arm—and only fade away in the lighter areas of his arm.
And there are a few other reasons why we may know for sure that this leaf pattern is not some kind of reflection. As I continue to discuss this, I will refer to the five pictures at the beginning of this thread; but I won't keep posting them here, to save time and space. Instead, I will refer to them as: PatternClose-up, Ambulance1, Ambulance2, Ambulance3, and Ambulance4 (these names can also be found, using right-click and "Properties").
The Ambulance1 picture has the strongest image of the red car and background, so let's start by taking a close look at that picture. Notice the curb in front of the car; then notice the ground (and sunlight with shadows) between the curb and wall. The wall itself can't be seen very much, because there is not much on the wall to be seen (refer again to the wall video, if needed). But you can see the top of the wall; it is a straight line from near the top left of the picture (a little below the paramedic's patch), and ending a little lower on the right side of the picture (in the bright spot). Above that line, you can see again the ground above the wall (and a little more sunlight reflection).
Now that you have a good view of the entire background picture (and not just the car), notice that the leaf pattern is more than half as tall as the wall; so if it was an image on the wall, being reflected in the ambulance photo, we should easily see that large of an image on the video of that wall—but it's not there! The wall in the video is almost completely blank.
However, there are some real leaves in the wall video; but they are connected to trees—not just hanging there in mid-space. Yet the leaf pattern in the ambulance photo is isolated, not connected to anything. To make it even clearer: notice again the line which is the top of the wall; it runs clear across the ambulance photo—not broken anywhere by a tree trunk, or even smaller branches. Also the leaves in the photo don't seem to come close to the size or shape of the leaves in the wall video.
Last but certainly not least: we can eliminate the leaf pattern from being part of the background image, simply by comparing Ambulance1 with Ambulance2. Compare for example the headlight of the red car in the two pictures; the pointed left end is straight under MJ's mouth in Ambulance1, but straight under the top of his forehead in Ambulance2. The background image has moved significantly to the right between the first and second picture; but the leaf pattern is in the same place.
Yes, a bit more of the leaf pattern goes behind the paramedic's arm in Ambulance2; but this is a very slight difference, compared to how far the red car has moved. And if the leaf pattern is inside the ambulance (not a reflection): then this slight difference can easily occur from a slight movement in the paramedic's arm, and/or a slightly different camera position. But if the leaf pattern were part of the background image, then there is no explanation for why it does not move to the right just as much as the red car moves to the right.
So we have three or four real strong reasons here, why the leaf pattern is not a reflection or part of the background image. Unless anyone can debunk these reasons, then we can move on to the next step: more detail on whether the leaf pattern is Photoshopped or not.