Proximity to the online store and a short shipping time is definitely no guarantee that the yeast won't be DOA. I live ~80 miles from Morebeer's NorCal distro center, and about the same from Williams, and always get orders the day after they ship. Once in a while I still get DOA liquid yeast--although to be fair, it's very rare this happens.
But if it's not transit time/conditions from the yeast bank to them, or from them to me, then the yeast is either being subjected to temp extremes while in inventory at the online store, or the yeast was dead before it even left the yeast bank. Either seems very unlikely so it's still a mystery.