AirBnB’s Terms of Service provide for mediation (which may only apply in the US, and like many mediation provisions in contracts, it requires that you use Air’s choice of mediators). In the EU, provisions may be quite different. Like others have said, you might need to hire an attorney.
I hope that what Air Customer Disservice folks told you was on their messaging platform, not just on the phone. If I had something like this happening, I would record every phone call with Air CS, but such recording in my state only needs the consent of one party to the call and laws may be different where you live.
I would try embarassing Air on Twitter and Facebook to see if you get a response. If not, it may be time to call lawyers. FYI you can’t sue for damages in the US but you can in the EU.
One US based host won a case against both Air and a guest for closing her listing because she had a pet toy that looked like a pistol.
See