We figured out how to make the shared verified list work. It's not the ideal, but it works just fine. Here's how we did it:
1. Create Dropbox folders for all of your verified lists.
2. Assuming you want to link 4 verified lists, In all of your projects click "Identified", "submitted", "verified", "failed"
3. Go to options=>advanced, and point your "verified" list at the verified list on dropbox for that server. Make sure that you check "verified"
4. Using the dropdown, Point "identified", "Submitted", and "failed" at the dropbox verified lists for the other servers.
5. DO NOT check "identified" Submitted" "Verified"
What this will do is let each server read the verified lists of the others, but not write to them. It eliminates the problems. We have been running 4 servers this way for a few days without issue.