Yes of course but it would mean that her statements were not accurate because I think to say she knew he had done it on the night and for him to have allegedly made previous actual plans to murder them would mean she was pretty thick not to realise . And she was not stupid was she ? Not according to her qualifications and her subsequent employment .
But I find it very hard to believe she did the ID knowing all she says she did .
Has she said she categorically knew on the night? Has she said she even suspected on the night?
I can't remember without going through her statements again.
She must have discussed things with JB afterwards at some stage though, perhaps she became more suspicious which made JB come up with the hit man story (if indeed he did).