I don't have much of this information you want, but from what I've seen on mpgh, google is mainly going after people that sent like 10+ pixels to one location. They deal with thousands of orders every day, not quite sure they're nitpicky enough to go after accounts that just got one pixel refunded/reshipped. In other words if you didn't do anything you shouldn't have done(in terms of the kind of things done on mpgh) you should be okay.