Hello,
If you don't find what you need in the tamAudit log files you may want to check the tam.log files.
These should be rotated similar to the tamAudit.logs and will show you who deleted what, when:
Example of a deletion event:
15558 1476810563726 End-System.6.Event root DESKTOP-B9SK4TI --- Remove End-Systems and Events Removed End-System for MAC: A4:77:33:33:2C:A0
Unfortunately the time is in time ticks, but if you open the log file using NetSight Console log viewer then it should covert to a readable time.
Thanks
-Ryan