JASRAC's info is submitted by the rightsholders, so the titles aren't just made up, yeah.
It's rare, but I've seen other games without soundtracks that just randomly have JASRAC entries for no obvious reason (Sega Strike Fighter is one that always comes to mind). In this case, rather than pointing toward a future soundtrack release, I think it might just indicate that Mitsuda is fairly proactive in making sure copyright registration for all his compositions is sorted out, being that he has
this page on his site and all.