In Kalanick's place, I would do the exact same thing regardless of whether the claims were valid.
2 years after a jury found that Ellen Pao was full of it, TechCrunch and other media still portrays her as a victim. Most likely they will do the same for Susan Fowler, even if (purely hypothetically) a court finds her to be full of it.
In such a media climate, you need to genuflect in the direction of all that the masses find holy regardless of the facts. At least if you are good at politics, which Uber is.
By whom? What do you think the public or the media would react when they see a young woman fighting with a multi-billion dollar company that is already in a PR crisis in a sexual harassment case? The truth is always more nuances than just true or false. If as a community we learn a good lesson, then all this is probably worth it.
As for Ms. Fowler, I don't expect her to be a neutral figure, and if you read her tweets, who called for boycott of her ex-employer based on false information, she clearly is not.