Everyone has their own personal hypothesis, but that's all they are our own theory of the events,only a small handful or one single individual know the truth, but the dinner party collusion reminds me of my own personal mantra, three can keep a secret if two of them are dead, people being people just ain't good at keeping things to themselves, guilt weighs heavily on some, a need to unburden to another, finding 7 at a table of similar 100% tight character is a statistical impossibility.