Well... you guys don't actually know where the DMZ starts and ends... and you can't actually see the Vrock (except for RJ and Marlowe)... so in truth, your characters might not know that it is outside the DMZ... But they could guess that from the fact that it seems to be invisible. (You can't see it, even though it is flying in open air. Marlowe has permanent See Invis, and RJ is close enough for True Seeing to work, unlike the rest of you.)
I don't really know of a good way to draw the damned map, since this combat is heavily dependent on having a vertical dimension... So let's just wing it and go with descriptions, OK?
Right now, RJ is on top of a 50 foot tall wall, basically where I have the Vrock labeled on the map. The Vrock itself is 120 feet higher than that, in mid-air. Marlowe has backtracked a bit towards where RJ is labeled on the map. The rest of you have begun piling out of the Pit next to him. Did I get all of that right?
Edit: Ah crap... I'll update the map, and write in numbers for the vertical dimension, I guess...
Edit2: I added a scale bar, instead of a grid. I don't feel like redrawing this crap with a grid... especially since the 3rd dimension makes it somewhat pointless. Just tell me (relatively) where you want to move to, and I'll add it onto the map. You can correct me if it isn't how you'd like.