Hi. I want to get back to the group about what I found with my squeak. After removing the headliner, I found a screw which appears to not have been originally tightened. I believe this is responsible for the sound of metal popping up and down a a thread of a screw (what I originally thought was a stripped screw). 700 miles later, all has been quiet - yet I do need to give Murphy and his law a bit of room here.

The screw which was the issue is indicated by the red arrow. The green arrows are the screws that I ran down through the cabinet, similar to Ron's initial idea.
I hope this helps someone.