No entry in the User Log displays the name change. I think the user log may actually be Syndol's User Essentials modification? Not sure. I don't know what tools is supposed to look like... Oh wait I have a xamp... K so Registration Logs and User Log is extra. Alright I don't know what addon adds the Registration Log but when I look at it it showed that there was 300 failed attempts to create an account on my site yesterday by spammers holy #$%!!! The pattern I noticed is that once the spammer fails with one email they'll try again with other username about 3 or 4 more times then it's back to trying to register with a different email. Disturbingly persistent...
Oh also saw a Server Error http://xenforo.com/community/threads/what-server-error-is-this.38900/
Anyway, none of that stuff told me who changed her name to Herpez Mouth so I guess I'll just ask her myself.