Jeane is accessed by having enough coins (awards section in menu screen) and using the payphone in the food court. If you have enough then you get a code (doesn't tell you a code, you just "have" it) and you interact with the vending machine. This opens the gate on the back wall and reveals a hole that leads to Jeane's shop.
To get Jeane's scenes, you then use the viewing glass on her, which initiates her scene quests.