If Shu and Petra are de facto translators in a talent-run agency, how did Elira monopolize sponsorships? Are there different JP contact points between the boys and the girls? Shu was able to wrangle the men and Elira usurped Petra as a manager through nepotist accolades? That's why Petra feels guilty that she didn't fight hard enough to maintain her role as an underpaid Nijisanji female-side manager. Then Elira gave herself the sponsorships and everyone agreed to it since she got paid scraps to do it? Pomu agreed and the rest is Millie and Enna giving fake-info to Elira to live out their mean girl fantasies against Selen. Enna and Millie are bullies and Elira is just a corrupt incompetent manager. It's probably something like this.