I've replayed the game about 3 times and still can't get scene VII for Nami and Robin. Is there any specific requisite like charisma, or room lvl to unlock?
No, it is not. This scene will appear in Dress room on the beach
If i choose to stay and let them get mad or leave them alone the scene does not appear after the event.
What do you mean? If you dont leave - you see their scene. That's it.
After staying the scene it's not unlocked in the scene gallery and I'm left with a blank space that says unlocks in act VII.