Just an update for those who are following this thread and were in the boat as me, AirBnB support ended up qualifying my case as EC.
They told me all CS agents do have a list of events that are classified as EC and the storm in Tahoe last Dec is on the list. So it was not hard to qualify if you can connect to an agent willing to review, understand your situation, and do a proper search on that list.
Hope this helps.