The event in question is saying we successfully found and deleted some malware. The user has the antispyware module installed.
The question on whether an Executive Reviewer can make a change to your notification rule is best answered by the ePO forum, or you could call McAfee Support.
On my server, an Executive Reviewer can only view events.
From what you describe, the events are still in the database, else he wouldn't show up in your Top 10 Users with most detections.
It sounds like something is amiss in the Notifications mechanism triggering off the received event.