It works! When Kiplyn
speaks the next Rule, the door makes a mechanical 'click,' and our Heroes are able to push it open and enter the next area (#6 on the map). This next cavern has a high ceiling and a slight upward breeze suggesting a 'chimney' effect that keeps the Caverns well-ventilated. To their right side, our Heroes see another deep chasm that slices to the northwest. Far below, they hear an occasional distant 'splash' of water. There is a 20' wide ledge running along the south edge of the chasm, if the Hobbets wish to continue to the west. On their left side, to the south, our Heroes see a well-worn tunnel; it is about 10' wide and tall, and does not count as a 'tight squeeze.'
OOC: I hope the map is clear enough to the new players? The sort of 'airbrush' shading represents unexplored areas at the edge of torchlight.
Full size image: https://photos.app.goo.gl/i9Egen9hVNnskCVf7