I believe you also have to get your popularity to 20 if you haven't already. You must also interact with the girls a bit, and have them trust you. You must discover Liz's kink, or the scene won't activate. You discover Liz's kink in the second chapter. Hope this helps
That's not the problem. I've got 100% completion (with >100 grades, discipline, & popularity) for 0.13.2, except for unlocking this scene in the Replay Menu. I've seen the 2nd version of the scene (w/ Liz's kink) several times, and the 2nd version was actually the version of the scene I saw the first time (in Ch 2 with ≥20 popularity). I had to use the Cheat Menu to reduce my stats to get to see the 1st version of the scene, but it still didn't unlock in the Replay Menu.