alum likes to make up stuff, so in her twisted mind she thinks that, nationally, there's a tier system because she thinks there are sororities out there that are better than others and these NPCs should be invited to present/colonize only, not the weaker sororities.

Don't know who her "Big 6" are, and frankly I don't give a shit.

Congratulations to the THREE wonderful sororities chosen to present at GWU. All are fine organizations, IMO, and GWU will benefit from having ANY of the THREE.