wow... you really posted it- thank you. I hope this helps in any way. I have a lot of little "side notes" to add to the conversation. I am having a hard time connecting to the actual recording, maybe it's just that my computer is being lazy this morning. I know that the interview took place the way it did for a few reasons.
1. The moment police asked her if she would discuss this, she said she would be happy to, then lawyered up so they couldn't talk to her. They were not able to get an interview, so Detective Nosack, (30 years as a homicide detective before this) just walked up to her door and asked if she would have a chat, and she was taken off guard I guess and said sure- come in. That is how the interview was achieved.
2. Detective Nosack said he trains police officers around the state on how to do interrogations. He said the first step is very low-key, just getting a base-line of how the person talks and thinks without any uncomfortable topics. The next phase is listening to their accounts of what happened, and the last phase is directly accusing them and seeing their reaction. (I probably got these stages all wrong, but basically it's an escalating pattern of some type.)
Detective Nosack said that at the end of the discussion, when he accused her of all of these things, she was just sitting back and smiling at him. He said she even laughed a few times- but she never got mad or stood up and said, "GET OUT OF MY HOUSE" like you would think someone would do if you'd just accused them of killing so many people. He said that her comment at the end of, "I hope that you don't really think that I am a monster" was significant in some way also.