It's a cool thing - poorly handled but how many of our mods have appeared in obscure places with no link backs. I know I for one have never been to Russia but H2O-C7 has been!
typically I think I would say your dreaming and it wasn't a copy, but like Mos said, thats the same angle, same cord placement, same base, same fasteners around the base stand, same... well... everything really. I'd call them man, skip past the e-mail and get someone directly on the phone. Its a lot hard to NOT give someone an answer when your already talking to them. Mostly just because I think you deserve credit. If I were in your shoes I don't think I would be to worried about the recognition from the players, just that the company had asked permission before they used it. Its just common courtesy.
+1 to what sixfootsideburns said slippery... I would call the game publisher and call them out on it...
You should definitely get some credit/something nice for what they did. You said you already have the game, but how about some copies to hand out to your friends? That wouldn't cost anything to the company and would be a nice gesture of them... And a bit OT, but related, in an FPS game (I think it was Vietcong II, but not sure) there was a photo of a Finnish airsoft team on a wall of the barracks They weren't asked for a permission, either, but I can't remember how the case ended. Kinda cool and lame at the same time...
The real smoking gun here is the tiny piece of cable peeking out from between the body and the support lug. People have speculated that the photos have been run through a program instead of just used as models. That would make it a bit more evil in my eyes. Copy is one thing but manipulating an original photo is another. There are others involved in this issue. I'll sit back and watch what happens. Here is another example. I think the photo is owned by a museum and they are not amused at all.
I just can't understand why a company would bring this on themselves! Its so incredibly easy to just ASK permission, chances are as long as they listed reference nobody was going to care if their photos got used. Wouldn't you think that would be the simpler way to do things in the long run? Tracking down who took the photo would be a simple matter of some phone calls and e-mails, and if you couldn't find them... just get another photo and try again?