I cannot find a list of those who was there fully.
International Order of St. Hubertus
"Thirty-five people were reported to have attended the weekend vacation."
"While sometimes referred to as a secret society, the Order has a website where it shows off members in long, green robes and displays the Latin motto Deum Diligite Animalia Diligentes” or “Honoring God by Honoring His Creatures.”
Count Anton von Sporck, the group’s founder, also shared Scalia’s love of opera, and has been succeeded by a line of Grand Masters ending with the current Archduke Istvan von Habsburg-Lothringen.
The former Grand Master, Archduke Andreas Salvatore von Habsburg-Lothringen, had previously visited Poindexter’s ranch for an event reported by Culture Map Houston that involved dressing up in traditional European hunting attire for bird shoots."