On your first question, I don't see how she'll get a DA to listen to her if the tape or disc is destroyed. As for the rest, in many states it is illegal to record another person's conversation with you without their consent. In all states it is illegal to record a conversation to which you were not a party.
See my Legal Guide Recording Conversations in Illinois
You need a lawyer because I do not practice in AZ (I am in Chicago, IL). Check with a lawyer in your locale to discuss more of the details. I do not think it is not legal to record a conversation in AZ unless one of the parties give their consent. That is not similar to the rules in my state so check with an AZ lawyer.
Good luck to you.
Again, check with a lawyer in your locale.
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