I recently came across the error in the image above when trying to move mailboxes from an on-premise hybrid server to Office365.
Why would this happen?
Configure your hybrid servers before you configure dirsync. During the hybrid configuration wizard , the wizard creates a sub domain 'domain.mail.onmicrosoft.com'
Now that the target delivery domain has been created by the Hybrid Wizard, We can run the DirSync configuration wizard. Select enable 'hybrid configuration' so once the wizard can see the target delivery domain it will add the smtp:firstname.lastname@example.org to the proxyaddress attribute in Active Directory for each user account.
So now when you try to run a remote move request, it will complete without issue.