I was serious about setting up that Volleyball tournament as a thread event months ago when I suggested it.

But as soon as I experienced a maxed out population instance of the map I immediately learned why it's impossible, because VRChat's netcode completely fucking breaks to the point where the volleyball gets more and more desynced the more people join the instance and the people playing get too desynced with each other.
The practicalities of making an event out of it would be impossible. You would need like 8 people in an instance max doing the actual volleyballing and then have it streamed to a watch party instance, and at that point it's just not worth it.