It is not stock photo. The unit is definitely a Pro instead of Premium. It's pictured together with its box, which has a Beyerdynamic sticker on it with barcode and labelled DT 880 PRO / 600 ohm Studio headphone with cable. Are you aware if there's a Pro version of 600 ohm? Thanks :)
Sounds too elaborate to be a fake, and as I posted above, I'm fairly certain the Pro 600 ohm model was sold in some parts of the world, perhaps just not North America.
Maybe contact Beyerdynamic and ask them if the model exists?