Bjork decides to climb up and see. There is a trapdoor, which he pushes open. There is a whirr, a thud as the trap door falls back into place, and Bjork's headless body falls down the chute and at your feet!
You move the trap door and see a 5' square hole, leading down about 15-20 feet. At the bottom appears to be a tunnel headed east. There are rusted iron bars about 1 foot apart, leading down as handholds/foot holds or a rudimentary ladder
The trap door seems just to be set in place, not locked, would probably need a string man to move it. No obvious traps are there. The floor of this messy room is covered in scattered gold and silver pieces