In a non-Clos topology, the process of clearing the session is performed on one leaf device at a time, until all sessions are cleared.
Since the MD5 password on fabric links is applied as part of fabric configure, there are no additional events that are generated as a result of configuring MD5 password. The Fabric Deployed event that is currently generated by Fabric service when a fabric is configured should be used as a trigger by other services that are dependent on the Fabric MD5 password for any of their operations.