I found this thread and found it helpful for 7-mode and wanted to update for cDOT:
You can use a combination of the following 2 commands to get the same information in cDOT at the CLI:
cifs session show -instance (user info)
cifs session file show -instance (open file info)
Use the connection ID field to link between the two outputs to establish the files a particular user has open.
To close a session or file you could then use:
cifs session close
cifs session file close
At least at 8.3+ you can also use the MMC to gather this information and close files/sessions if you have the appropriate permissions.
I am unsure about other methods like Powershell.