That list of trophys is accurate, the game gives a description of how to get them even if you haven't unlocked them. They translated them correctly, or at least for the most part they did. Also, I figured the secret ending was unlocked after you beat the game, mine just showed up in theater mode after I beat it. I only had three trophys, so getting 20 trophys isn't the requirement for unlocking it.
Have you checked theater mode, Sora The Key? It should be in there, that's the only place you can watch it after you finish the game. Yeah, it's 1 HP. Don't think it's possible to actually get lower than that without hacking the game.