I've found the exit and the girl but i can't interact with anything in the exit, so i'm guessing that something bugged but i'm not sure what exactly.
Viewing post in Maiden Chateu - Bug fixes of the Full Game! comments
Just found the bug and patched it out in a new build, you were just a couple rooms from seeing the ending. It's weird though, I didn't encounter that bug nor did others for the 2 years this was out. Anyways, just transfer your save to this new version. If you don't know how to transfer save files of RPGMaker games then just reply here and I'll tell ya.
Anyways, good day! And have fun with the remainder of the game.