Also, for the construction of the tunnel, I was thinking thick black fabric, almost like canvas. Or maybe a burlap so that when people rub against it it feels rough and unpleasant. We can form the tunnel by getting rounded PVC piping or a malleable yet strong wire and forming a bunch of them into circles and attaching the fabric to them.
For the sounds, I agree with distant gun shots, screams, and crying, but not as a constant. Maybe some ambient jungle noises like rustling of leaves and twigs snapping mixed in to make it feel like the people are walking through the actual world the woman do when they hide from the soldiers.