The expat board abroad is a very good idea.
One of the worst days of my life was the infamous 9/11.
Previous day my parents told me they were flying to NYC. Their arrival time closely matched the Towers attack and they used to stay at the Sheraton/Hilton (?) Millenium at ground zero but time they went to another hotel.
When the first info reached us i got desperate. This lasted over 4 hours of desperation and fear.
Comms with NYC were broken.
I went to a board I used to frequent and contacted a user with NYC as part of his handle. He gracefully located my parents and me within a couple of hours. They were fine but shocked, they were walking around Canal St. when the planes crashed.
The hotel front desk didn't have them registered since they had arrived quite early that day. Awful day.
You might get lucky and find someone willing to help that can go knock on the door for you.
GL
Iz