As for why they've opted not to disclose the information, it's likely for use as blackmail because there's no way a person like her wouldn't pull more shit in the future. Plus if they try to crush her reputation now she'll likely get desperate and who knows what she'd do then.
Another possible reason is that it would implicate not just her and her manager, but her entire family and agency as well. Which might cause production issues for this movie because remember, the director's her uncle.