Just checking out if there’s any new report in Teams Admin Centre and there is ! for Teams live events. Not sure when this came out but lets have a quick look.

click on the event and get more info

This is great for live events to having reporting and viewing event information

Microsoft Doc link to the breakdown of the report

https://docs.microsoft.com/en-US/microsoftteams/teams-analytics-and-reports/teams-live-event-usage-report