Pop a card in it and see what the image numbering says. If he only charged it once, I doubt he would have gone through the trouble of doing any renumbering, etc.
Thanks!
I asked him. The very first photo he took with this 5DS R has the file name of 3K5A6626.jpg. He used this memory card (which came with the camera) in his previous camera (5D MK III) and the last one I took with the same memory card on the camera today is 3K5A8040.jpg. So if these numbers corresponds to the shutter count it would be 8040 - 6626 = 1414?
This makes sense since he told me that count should be around 1000.

