Mei was there! She came because she was expected to be there and is friendly with Rhysh. She was a little more withdrawn than normal, but probably threw herself into conversation with those she knew and went to find a quiet spot to mope for awhile when she was Done with evening, but couldn't leave because it was too early still.
Margo went to go check out whether Rhysh's mouth was worth it, but also because she likes dressing up and talking magic.
Regina was there because of the law firm and she's expected to make nice (she was not nice), and George would have gone, but Katie being sent back derailed that plan and he's off in the woods with his brother right now. Sirius was only there if Bonnie decided to attend, otherwise he would have been at home moping.
Keith might have came? He went to the Symposium for Atreus, Sabrina, and whoever else he might have known there that was going to speak, but he only went to this if Shiro went.