Ensure you have software version up30r2 or above.  This option can be found under Pool menu > Shares > Options for share > Protocols. (then scroll to the bottom)


Enabling this option will create a hidden directory .smb_audit_log inside the root level of the dataset. All events will be monitored and listed in a corresponding log file.  You probably will need to create an admin-only share at the root "/" of the dataset so that you can monitor the audit files.



Understanding the file - 


This indicates a successful deletion (unlinkat | ok) of a file


This indicates a successful rename of a file  (renameat | ok)