to be fair there is likely more permissions that need to be secured other than just lily saying "go for it" HOWEVER as far as i can tell the permissions were acquired from all relevant parties, especially considering i have not seen a single person who could claim rights on the song has come forward to back up anycolor's statement
the only thing i can think of would be internal permissions. For example its
possible that talents needs explicit permission on date and time for a video to be posted, and selen may not have done that correctly. or the suggestion that ex-talents being shown in the video could have been the cause, those things
are anycolors IP and they have every right legally to take down a video they control that uses their IP in ways they dont like
overall though niji did a big dumb, they pulled a video, gave a half assed response, ghosted everyone by giving zero communication on the subject, then fired selen with no warning and are trying to claim its no big deal
if they werent already falling apart at the seams they are now, too many eyes watching the company looking at all the bullshit