> Why, if, as you say, airbnb was being as helpful as possible from the get-go, did the victim write that second post?

Speculation:

Airbnb offered money and support if she agreed not to sue them and not to feed the press the negative story about the service. She refuses to commit to this, they refuse to pay her without it. None of the two parties wants to be transparent about this part of communication. Technically, no one lied.