Ah, gotcha. I can now confirm as well that this is the cas. Just skipped through it and the girlfriend thing with Emma is what allows the scene or not.Pretty sure it has nothing to do with Berry at all but rather whether Emma is your girlfriend or not. If you take Emma as your girlfriend then Berry won't let you have sex with Elizabeth because you "belong" to the family and she won't let you cheat on Emma with some rando (Emma technically gives the family permission to share you).
On the other hand, if you aren't Emma's girlfriend then Berry has no hangups on it and lets her friend play with you.