Is there any way to check which mailbox has not been rebasing?

Q: Is there any way to check which mailbox has not been rebasing? We are going to distribute the Outlook tool to each user with SMS and running it on /quiet mode to rebase the default profile once OS install done. Then want to use Exchange tool to do rest.
A: Have you considered running the Exchange tool as your primary solution? And then pushing the Outlook tool via SMS to the NonExistent.txt (no time zone stamp) mailboxes? This is a less user-dependent solution (you can run the Exchange tool silently).