@Snorre-Lothar0
You would have to contact airbnb to have a reservation cancelled under the "extenuating circumstances" clause - there is no way to do this cancelling through the site.
Go to the discuss tab above, then help, and find the community help guides. There is one guide dedicated to contacting airbnb.
With each superhost announcement I get the following by e-mail:
Priority support: We move Superhost calls to the front of the phone queue. To get in touch fast, call (+)47 21 61 16 88 or tweet at @AirbnbHelp.