[Vaskerry]

Spoiler for Theory Rokkenjima:

I believe that Yasu as the inheritor got everyone to play along because remember EVERYONE NEEDED MONEY, everyone except Battler. She may have even gone as far as getting Rudolf/Kyrie to get Battler to the Family Conference, which would explain how Kyrie/Rudolf planned ahead and decided to leave Ange at home. I mean, you just don't commit crime over theoretical gold ingots and a legend of a golden witch, Yasu probably talked to the siblings after becoming the inheritor a thus revealed the reality of the gold and that she would give them money if everyone played along. Which explains how relatives got cards after the acciddent in Rokkenjima, someone planned everything ahead. Ange just had to go and check Kyrie's mailbox to see if she had a card and the mysteries would all be solved. I also believe Kanon doesn't exist or at least doesn't have a body to claim like Shannon, because it's the only Corpse Beatrice <Deletes> with magic, however this would only be true if we support the <Trick> ending, I believe in the <Magic> ending.