Challenge Failure Buried Underground

I am having an issue completing the Buried Underground challenge in the current tome (my last one until you open the last page!) but it doesn't seem to matter what I do. I only have one more component to complete (hook in basement) -- which I have done up to ten times successfully, but not seeming to complete the challenge. I've gone off the challenge both to something else and also as a quick reset, like with some of the other challenges, but this one seems completely broken.