>>67652209They didn't "want" to fire her because she was (next to Pomu) apparently the biggest female NijiEN talent. Announcing her graduation or, worse, terminating her right after Pomu's leave would have been bad optics - two of your biggest entertainers abandon the branch, that's a loss in viewership and profit, to some extent.
She doesn't want to leave on her own because of several reasons, but part of that could be sunk cost fallacy or learned helplessness. It's possible she thought that she could learn to play along with the system but now that she was pushed past her breaking point, she'll want to leave. Again, management would never have let her announce a graduation so close to Pomu's for the sake of their bottom line, so even if she did want to, she can't say anything right now.