It's unclear to me from the photo, but you are sure that this is a sympodial orchid, correct (not just 2 plants in one pot)? Just because at first glance it reminded me very strongly of a Trichoglottis, here's a link
http://www.orchidweb.com/images/Trichph1B.jpg
and here
http://www.orchidboard.com/community...ree-mount.html
Trichoglottis is vandaceous monopodial orchid and isn't super common to come across randomly in US so it doesn't seem super likely, but if it's not sympodial that would be my first guess.
If though it is def. sympodial, then I would venture reed-stem epidendrum or possibly a dendrobium, although something about it doesn't look right as a Den to me.
Good luck!
Sara