I just encountered this same problem due to a power failure to my host. As you noted, the directory contains one or two broken files that cannot be deleted. My solution was, using the datastore browser (and after unregistering the VM), to create a new folder alongside the old one and move all the files to that folder (and re-add the VM to the inventory). I can't delete the old folder, but at least I can power on my VM (I was prompted whether I moved or copied it - definitely moved) and get it working again. The corruption is still there; I can't delete the old folder using either the datastore browser nor `rm -rf` but it's fine for now, I'm in the process of moving to a more stable host anyway.
HTH,
- Oli