This is a comments thread for the following album: https://downloads.khinsider.com/game-soundtracks/album/persona-4-golden-2012-ps-vita
It's in the Persona 4 Golden (Windows) page of the song that your looking for. Top song of the list. I hope that was what you were looking for.Wait BGM 50 is different. I saw a YouTube video of a different song under the name BGM 50 that's unused. It was only in the PC port of Persona 4 Golden if I remember correctly. It's like a beta version of Marie's song