The answer should be in the game thread. Else, well, just think about some boss you can only fight after completing the game. Should be obvious if you played the game and not used a full save.
If I had used a save, I wouldn't be missing a scene, now would I?
The ??? boss was the 'final' bad guy. Who is now de-powered in the church.
I found the hidden areas. And even killed the big armor in the gladiator arena after I unlocked the scene.
Edit: When I used the search yesterday, the only thing that came up was the translation. Today, I see the thread.
The actual missing scene was a joke, though. Sigh.