But the buttons are simply not there is there are more than four enemies. It is a known quirk of the way the game's UI is currently set. Same as with victory and loss sex scenes not showing author credits because they have enemy portraits occupying the screen instead.
The ones with Kinu? I think most of them are canon considering there is one where Komari explains why the den kinda fuckin has a dislike of the PC outside of the whole Isolationists.