I don't think we'll ever find out! Buchheim is still hedging the issue (or Simone is) in "Der Abschied." My personal feeling is that Simone, at least as he portrays her, was too selfish and shallow to risk her life for as desperate a cause as the Résistance. She liked playing around the edges, with her black-market dealings in interior décor (almost laughably petty, when you think about it) but people who were really with the Résistance had to be psychologically prepared to die for the idea of a free France. I just don't see Simone having that sort of nobility of character--or madness, depending on how you look at it. She loved taking small risks, and seems to have really gotten off on playing "look how close to the edge I can get without falling over" but that was a form of self-aggrandisement (or so it seems to me) not strong national feeling. Can you tell I'm not wild about Simone? It's been suggested that Helga, the super-competent housekeeper who pops in on Buchheim when he's working in his "Bude" in Feldafing, and later rescues all his stuff before the government spies can get it, is actually Ditti, Buchheim's second wife. Now, there's an admirable female character! However, maybe a male reader would feel differently about the two women . . .
Cheers,
Meg