€1,950,000 5,124 people for the first event goal

I think it should be on the moon with a Black-Mesa-branded rocket (with Gnome on-board), for thematic reasons. It’s no Xen, but you could probably add some decorations and even without that it’d be a better match than italy.

Not sure about dodgeball though, I think area combat would fit more as well. Just make to have first-aid stations and have everybody sign waivers.

…or maybe you should just do free meet-ups with people to play dodge ball or talk/play about your favorite games etc. (and maybe you’ll find some overlap) without it being some record-breaking event?