2007 Ford Mustang wipers, windshield & visibility problems

2007 saleen mustang,(ford), no rear view. Back window is blocked by spoiler and back side windows are replaced at the factory with solid fiberglass. Backing up or changing lanes after glancing over either shoulder brings no visual help. This constitutes an enormous blind area and is very dangerous.

Noticed one day that my rear window what foggy looking while driving to the point you can not make out shapes or objects. Cleaned the vehicle thinking it was dirty but not in this case. Had it looked at and I was told that it was distorted from bad material or not put together right. It is still a factory window and ford refuses to do nothing with it. Now I am having AC problems, warm air blowing on the driver and semi cool air on the passenger side.