Honestly I know others will dispute this but I don't think she did know and to clarify this is only a feeling , but I think the police possibly spoke to her earlier than we think and convinced her he did it and coached her how to embellish things that had happened in the past . I am not sure why exactly she was convinced but I do genuinely think a t the time of the funerals and the morgue visit she did not have a clue , but that does mean her statements are not true .
That does not implicate either way whether Jeremy is guilty or not , perhaps she went along with the police because she did think he was capable , I don't know .
But nothing that she said in her statements about his plans of poison or burning etc can be proved . It was her word against his . So quite clever really .
IMO