I finished over an hour slower than her when I ran it 2 years ago and had no issues with receiving a medal, there were plenty of buses going (though the queues were quite substantial, that's fair, but that's going to happen when you're moving ~35k people plus their supporters about.
Looking at this article all three of these ladies who contributed to it were within 10 - 20 minutes of the cut off/sweep time. So why does it affect little Kelloggs who was home by the time they'd all finished?
Like I said, when I finished in ~5:20 when I ran it, there were plenty of people still around, bananas and water etc., we walked about 15 minutes to the car that my OH had parked nearby so no issues getting back to our hotel (except the expected traffic). Wonder what went so wrong this year then?