Really great investigation. It’s much harder as a small business to get refunds out of AdWords for fraudulent clicks. I’ve fought the same battle, often unsuccessfully. When I was at an agency spending millions of dollars on behalf of clients, it was certainly easier.
One question I do have looking at your data is more detail on the actual keywords, match types and ad creative used. Often, there are more fraudulent clicks on some types of keywords where an audience is being reached that isn’t intended.