We'll get caught if we always have the same answers. In this way your child has offered her friend help but at the same time protected herself. Make it clear that you're concerned about the cause of the cheating, then offer to help him organize his notes so he can write his own report. But you can explain that most teachers have different versions of the same test. They change questions around for students who are absent or if an unexpected assembly has disrupted the schedule.
Experienced teachers know how to discourage test information from being communicated.
Explain that lying about it only doubles the mistake, and teachers are more likely to forgive if the dishonesty is acknowledged. Of course, a lecture on ethics won't help if a child is overwhelmed with fears and insecurity. I support you, no matter what, if I know you tried to do your best work. Maybe you and your child need to talk about academic expectations. It's unrealistic to think a student will make A's all the time.