I know that one NXN runner from Northern Virginia, where Kate Murphy is from, had a 16-hour journey, from wake-up the morning of the travel to arriving at the destination in Oregon. Yeah, some kids have done very well despite this different kind of endurance time trialing, but I would guess that the longer the travel (start at home to finish line at the Portland [NXN] or San Diego [FL] hotel), the greater the odds of running "below par" in the big race.
Of course, travel is just one factor. That is, one potential factor. And, like I said, some kids do great despite the distances traveled. Take Drew Hunter and Weini Kelati a year ago at Foot Locker. Both champs, both from far away.
Annie Hill, it has been reported, has been plagued by some injuries or illness this year. Not sure how this affected her last Saturday, but I don't think anyone has mentioned the possibility of injury/illness. The reality is that even the best athletes, if at all under the weather, can be off of their games. Take D.J. Principe as an example. He will bounce back, even if letsrun.com opinions have shifted.
And then there's Drew Hunter, who twice obliterated indoor mile records despite sickness last winter! But, then, he's one of the all-time greats.
Someone reported that maybe Kate Murphy fell. Does she look mud-smeared in any race video. (I haven't looked.)