Like the title says, why are there no songs from Dirge of Cerberus in Theatrhythm Final Fantasy Curtain Call, while there are songs from the original FFVII, Crisis Core, and Advent Children?

 

And to go with this question, does anyone know if there are any plans for making a third Theatrhythm Final Fantasy game? 'Cause if they are planning on making a third one, I'd really like them to include songs from DoC this time, and I would personally absolutely love it if they included both of the songs that were performed by Gackt in DoC, "Longing" and "Redemption".

Unless someone here secretly was an influential figure on the game's development, I don't think anyone can answer why Dirge of Cerberus was left out. They probably just thought that they had enough from the VII compilation already. As for a third game, I believe it was confirmed that Curtain Call would be the last Final Fantasy game in the Theatrhythm series. They made a ton of DLC so they wouldn't need a third game, if I remember correctly.

nobody wants to remember Dirge of Cerberus, that's why

I think you kinda answered your own question there: It had songs from FFVII, Advent Children and Crisis Core. They probably felt four titles of the same series was a little too much. 

There are zero plans for a third Theatrhythm Final Fantasy game on Nintendo 3DS.

 

Dirge of Cerberus was shockingly received, its the third lowest rated game in Final Fantasy history, hence why they haven't done anything to follow up that secret movie.