Did you do this via cheats? The Delinquent has to be a member of the party the first time you pass through the area, which includes triggering all the cutscenes.
I did this using the 'add Delinquent to the party' spot that opens up after reaching the end of the current content(if that counts as a 'cheat'), cuz it was kinda necessary to get the solo table art sequence unlocked. I guess you can do it without that by backtracking, but it's still that I think a lot of people will do it that way, and potentially run into that bug themselves.