I don't think that Jana has as big a criminal mind as we seem to think she has. The writers seem to have dropped the ball on this; but I believe that Adrien somehow forced Jana to lock Colleen and Kevin in the room ( whatever the place was,) to kill them by suffocation. Of course Jana has this "Dexter" type quality in her personality, but I don't see her as a pychotic person. Thus, I doubt that Jana has any relationship with Jeffrey, and his criminal minded tactics. Jana is simply a very nosey woman.