Honestly Jessica I could see potentially. But Moira, as much as I want her to be part of the blackmail plot, I can't see her as wishy washy as the blackmailer is right now. She is someone who does things with a purpose and if she needed something from Ashe she wouldn't go at it in such a roundabout way. And Jessica I have a feeling has other secrets, but from what we have, without my feelings, I could see her as the culprit. Siri is always on the table, but her motives are weak, unless it is an unassumed hatred of duplos since she is basically a stranger. Isabella, as some arguments for and against her, but the game did not give us a strong smoking gun like with Del. She also seems occupied elsewhere with the issues with her mother. But I admit it is like the game goes out of it's way to give everyone an alibi to not be the blackmailer. Some of the conclusion we come to might be false.