Docmal -- Me and my Brother are currently writing our own open source parser. Recently I was notified that MoX handles the Scoundrel's Disappearing Act. I reversed engineered it and basically MoX watches for Disappearing Act and then sets a grace period (the period in my parser is set to 15 seconds) for you to enter back into combat, else it starts a new fight.
If you want to take a look at my implementation for the handling of Disappearing Act, I can PM you a link. I might need to change the requirement of the exit event being 100ms prior to DA though, if that's ever out of order.
I guess great minds think alike. This is pretty much how I implemented it. It was pretty easy since I already had a grace period after an exit combat event due to the out of order appearance of combat activity after an exit combat event.