Thank you. We had the same issue and your steps helped. 

One additional thing to call out.  Had to reboot the ACC to perform the module uninstall as we kept getting module in use message.

Note: if you have "Exchange Powershell" option disabled in Airwatch Cloud Connector config, the PS commands go through SaaS environment and have no dependency on ACC. 

Also, if the issue persists, check the Azure AD signin logs for the account [non interactive signin's]