@Renato---Louri0 Indeed you have a special situation with the Olympics. You would think that if a guest were to cancel there would be people in line ready to rent your space even at the last minute. If that were to happen, you would get 150% (cancelled payment plus new guests). That said, the Super Strict cancellation policies are granted to a very few hosts and only by invitation. I noticed with interest that the host service fee increases to 5% for those who are granted that cancellation policy.
You can certainly ask Airbnb for the Super Strict cancellation policy, but I wouldn't have very high hopes of getting it.
Let us know if they give it to you!