How i can unlock this scene:
This took me ages too. It's during the Dethroning the Queen quest. I think you have to have *not* freed the nurse from Kate's blackmail during Twisted Desire (though haven't tested personally since I used the chapter select feature; but based on the circumstances chances are good that it's a requirement). Then during the dinner, when Maxine asks you to take a picture for her, you have to select Kate and then choose to wait for a better shot. She and the nurse will disappear and you can target the kitchen. Stay and take the shot for the scene