It would have been a blast if a young Fritz Donner had somehow been there. :D
That said, you've got the House leaders with their family and their partners; names are dropped at the wedding reception scene in Riposte. From memory, the named guests include
Michael Hasek-Davion & Marie Davion, Morgan Hasek-Davion, Quintus & Tamara Kearny Allard, Daniel Allard, Riva Allard, Felicity de Gambier;
Katrina Steiner, Morgan Kell, Jeana Clay, Misha Auburn
Maximilian Liao & Elisabeth Jordan-Liao, Candace Liao & Justin Xiang Allard, Romano Liao & Tsen Shang, Pavel Ridzik, Alexi Malenkov;
Takashi & Jasmine Kurita, Yorinaga Kurita, Akira Brahe;
Janos Marik & Brownwen Rafsani; unspecified "Marik family" members
Jaime Wolf, Scott Bradley
Cardinal Flynn (New Avalon Catholic Church), Cardinal Maraschal (Tharkad)
ComStar personell on site included Julian Tiepolo, Ulthar Everston; Myndo Waterly is present on Terra but not mentioned during the wedding proper.
All great Houses brought extra entourage to Terra who weren't invited to the wedding proper and stayed at the hotel. That's how Michael Hasek-Davion brought Anton Vitios and how Romano Liao brought Thuggee assassins.