I hate to break it to you but you are more than likely SOL. You should have definitely got the police involved and had them tell you they do not respond to private property accidents. It is not too late now, however, they will more than likely not be able to determine “fault.” At minimum, they should file an incident report and contact the other party involved. I am sure her story will have changed. It appears Progressive told you they can’t make a liability decision until they speak with their insured which is an appropriate response. Good Luck!
By the way, what exactly happened?