I went back and tried different choices to see if I could find what I missed, and I got the scene. The first time I met Tom, I asked him for help, and I picked the "it turned me on" option, but then when I met him the next time, with Lei, I decided to stand up for myself instead of trying to side with Tom. When I went back and did try teaming up with him, it later led to the scene with the photo. So if you do what I did the first time, the game thinks that he put his number in your phone and you talked later that evening, even if that never happened.