They headed out to see the keynote at 9am and I think they'll deal with the problem afterwards. Priorities, and all that ;-) If I find out what happened and it's relevant I'll report back.
They got in touch with AirBnB; AirBnB sent out a message to nearby hosts asking for emergency assistance, and a friendly host in the area was able to pick them up and give them a place to stay for the rest of the week. It looks like they may have to pay some fees and extra for the difference in value of the location, but overall it's better than sleeping on a bench in a park!
Thanks!