You are relieved to discover that the elevator still works and, therefore, you use it to shuttle one-by-one back to the main lantern chamber. It is dark there, since the green lantern and its flaming rock are now tucked away in your gear. But, after checking around carefully with your portable floodlights, everything is exactly as you left it. The lantern chains are all empty (because you have the lanterns) and the sarcophagus still points at the eastern alcove, where the elevator that squashed Marcus is sitting open, waiting for another "passenger."
The hole in the floor awaits. Shining floodlights down the hole reveals quite a lot: the shaft leads down about 60 feet and is deeply pitted and scarred, which should make climbing down relatively easy (DC5, so by taking your time, you should have no problems). At the bottom, the northern half of the shaft opens up into what is presumably a larger chamber. You can see the wreckage of a metal elevator cylinder on the floor there.
You do not have the required permissions to view the files attached to this post.