Even if she broke the law when making the recordings, it's not clear that the recordings can't be used in court. [1]

This would be different if it were the police illegally procuring evidence, under the 'fruit of the poisonous tree' theory, but here it's just a private citizen. So while she could surely be punished for breaking laws related to recording people, that doesn't seem to foreclose the possibility that she could use the recordings in court to prove her case.

1: https://acitylawfirm.com/recorded-conversations/