Sorry for the necro, but this is exactly the issue I have now (6 ears later), and other more threads are slightly different (they have error messages, while on my insync, no error is shown). Plus, it never got reply from the dev team.
I also noticed that new files are taken into account, and fear that removing the folder locally myself will delete it from Drive, even though they are shared with another account I also have control of.
In my case, the parent directory is shared, so the directory is only shared indirectly; I fear that removing the folder will register a sub-folder removal on the parent directory. While removing a root shared directory wouldn’t worry me, as such shared directories are generally kept on other accounts.
By the way, I use insync on both accounts simultaneously, if this matters. It means I have 2 copies of the shared root folder, with a different set of sub-folders synced on each side. However, some of the folders are present on both sides, yet only one insync account recognizes the Sync, the other is a ghost sync.
I tried to re-sync, then re-unsync, but the folder is still there on the unsynced side.
I guess I’m gonna pick a test directory and try a few things like disabling share or removing a folder after adding a copy with a different name, but it will still just be a workaround…