If there is another scene with Logan and Tyler, Elli will be the one who leads and tries to manipulate everyone into something really "wild". And so I would suspect Elli brings her mother into a situation with her very early at this event after it is impossible for Sophia to explain afterwards that Sophia and Elli are actually mother and daughter (mother and daughter interact sexually with each other via kissing goes out). Or let the secret be exposed. So if Sophia lets things go at this event and the secret is kept, she will at the same time get rid of Logan as the future son-in-law. In my opinion it will be less about the virginity of Elli than about keeping the secret of the sexual intercourse between mother and daughter.