Desktop App - Selective Sync not showing all folders

We have a lot of files on our company Dropbox account.  So much that we absolutely can't have our entire library indexed let alone synced.  For this reason, the 'Selective Sync' tool in the desktop app is our primary means to add new project folders, and remove old ones from our local systems.  To be clear, we do not avoid indexing our library for space-saving reasons - we are fully aware that an indexed file (set to online-only) takes up no hard drive space.  We avoid indexing because we currently hold ~100TB of data and the indexing for this quantity of data is a multi-hour process every time the Dropbox app is restarted.  When the app is first installed this indexing process takes several days with 1GB download speeds.  As this posts Subject suggests, our selective sync window is now missing MANY folders that are visible in Dropbox web, and this is a major issue.  Dropbox support staff has provided the following steps for resolution, but the issue persists.

 

- Ensure the Dropbox Desktop application is running.

- Ensure the Dropbox Desktop application syncing status is 'up to date'.

- Ensure there are no special characters in the affected files.

- Quit the application and restart the device.

 

They provided one additional possible fix, which I'll include shortly...  But to reiterate, we have ~100TB of data, and to index our entire library takes several hours after restarting the Dropbox Desktop application, and SEVERAL DAYS from a fresh installation of the application.

 

Dropbox Support's final solution was to 'unlink', then 'relink' our Dropbox account to our computers.  This sounded like a solution that would have our team losing hours (if not days) of productivity due to indexing.  I expressed this concern to Dropbox Support staff, and the assured me (multiple times) that this would just be a quick process in which the Desktop Dropbox application would take a look at all the files in our Dropbox account and likely be able to find (and add) the missing folders to our selective sync list.  Dropbox Support staff said, "this will not affect any of your selective sync folders."

 

We had a single team member test this final possible solution, because I suspected the Dropbox Support staff was just reading a script and didn't have the experience dealing with this quantity of data that we've been maneuvering for years.  So it came as little shock that Dropbox Support staff in fact WAS NOT able to fix the problem, and in fact made it hundreds of times worse by suggesting a solution that (contrary to their assurances) essentially reinstalled the Dropbox Desktop application and has one of our team members in the midst of a multi-day index. 

 

Bravo Dropbox Support.  Some knowledgeable advice would be appreciated moving forward.

 

If any community members have found a viable solution to this, we would greatly appreciate advice.  If Dropbox Support is able to find a solution in the meantime, I will repost.