I wonder if you could completely unlink all your OD and ODFB accounts (as in doing a reset), and then add the ones back that you want? I was just reading this article about how to reset your OD. http://www.thewindowsclub.com/reset-onedrive-in-windows-10
To reset OneDrive type the following command in a Run window and hit Enter:
Ideally, it should sync all the files again. However, if the OneDrive setup fails to start again, proceed to the next step.
In the Run box, copy-paste the following command and hit Enter:
Thanks for digging into this - interesting!
On another subject - can anyone get a demo tenant? Do you have a link about this? Thanks!