Would it be possible to make a ProcessMonitor log of what happens when you navigate into the folder?
That should show us if it's trying to open the file with a # in the name, and maybe getting blocked by something, or opening the wrong path for some reason.
Might also be worth testing what happens if the script that adds those other columns is disabled. It's possible that (or the underlying components that ultimately get the data for it) is keeping the files locked if they have a hash in their names, maybe.