If "Abandoned Mine" is abandoned, then why is there still at least two guys in it?
I think it's just one person. The man in the background is holding a lantern slightly behind himself, and the shadow in the foreground appears to be his shadow. You can tell from the shadows along the wooden supports that the lightsource is from the back, rather than from the foreground.
For me it doesn't seem, that he holds the lantern behind himself. His arm is in front of him. But even if, it makes no sense, that we see his arm, which holds the lantern, in another position as the real man does; and if so, there had to be a shadow for the real man, to the shadow in the foreground. I think this is just the shadow of the man who takes the picture.
And there are two guys in, because they are discovering it right now after hundreds of years. You know, people like visiting Ruins ;-)