Dirty Airbnb in Chicago

On a long vacation with my wife and 2 kids, I did enjoy an spectacular apartment in South Boston using Airbnb.  Next we flew to Chicago, using Airbnb again, I found a “CAVE”, dirty and a totally mess! I immediately left that disaster and notified Airbnb about that situation. They encouraged me to talk with the owner, I told her about the mess and dirt, she never disputed this issues.  I sent pictures to Airbnb, some was really shocking and I felt confident about my refund. Airbnb answer my request, giving me back 27% of my fee, telling me that I cannot prove my complaint and this is it. Because I canceled my reservation, of course, I can not write a review about my horrible experience and warn other users about this scary situation.