[JollyElm]

The card holder edges--top, bottom and side to side--are perfectly parallel to the top, bottom and sides of the picture he submitted.
PERFECTLY PARALLEL. A PERFECT RECTANGLE.
I used the selection tool in photoshop (dotted line) to illustrate the point in this blow-up.

So the Wagner is absolutely flat in reference to the photographer's vantage point. That occurring naturally is as close to impossible as you can get.

I don't know the guy, so I lack a horse in this race, but he obviously held something (perhaps a graded card), took a picture and then superimposed a 'professional' scan of the Wagner in front of it.