I doubt the EXIF has been changed at all - what would be the need?
The flashes are saying that they didn't fire because they are not linked to the camera, but to the sensor setup - so the camera never sends any controling signal to the flashes.
This is further supported by the 0.5sec shutter speed, far too slow to really capture frozen motion unless the camera settings and lighting result in a perfect underexposed photo (black) and then the flash itself provides all the light in its microsecond exposure time.
Ok, so knowing that some sort of flash trigger was used, this all makes perfect sense.
The problem I still have....... How do you get the blurry shallow DOF look on something that you clearly have in focus.
I would think that since the water is perfectly in focus, and the tinfoil is reflecting in the water that you would get a clearly focused reflection of the tinfoil rather than the blurry OOF circular bokeh indicitive of shallow DOF. It doesn't appear to have been added in post, or be the product of multiple exposures.......
I'm confused. (admittedly, confusing me is not hard to do)