I was only doing about 10mph because a lady with her toddler were ambling across the road in front. I heard a pop and definitely felt the stone come out from under my tyre. A split second later the window crumpled! Anyway, I haven't heard anything from them today, so maybe now that they've had the sense to phone their insurers they'll know the deal.
It's nice that you were concerned but as others have said sod all to do with you and TBH you should have just carried on where you were cycling to. You could be giving yourself a whole load of grief by getting involved and giving personal details that you not needed to do.
IF you had crashed your bike into the car then thats a different story but as no contact was made its an "act of dog"