Parking Lot Accident

This question regards an accident that occured in a private drive in Ohio. The parking area has several parking spaces that run perpendicual to an alley. The area is directly accessable from the alley in that you turn from the alley directly into an available space. The incident occurred on a move in day nearby a college campus in which four other students and I were moving into a house we were sharing. I had my father's truck pulled into one of these spaces and one of my roomates arrived with a truck and trailer. When he pulled into an adjoining spot, his back left scraped heavily against the front left fender of our truck. It is my father's truck and he was present when the accident took place. I, as well as an additional roomate, also saw the accident occur. We decided not to file a police report and instead my father was going to take the truck back home and get an estimate of the damages. The individual who hit my father's truck, my fellow roomate, acknowledge that it was in fact his fault but wanted to consider paying for the damages out of pocket instead of running it through insurance, depending on the amount of the estimate. We had no problem with this, but we did notify our insurance company at the time of the accident. So a couple of weeks passed and my father gave me the the estimate and I in turn gave it to my roomate. He then told me that it was his father's car and they were going to run it through the father's insurance company after they decided that 650.00 was to much to pay out of pocket. A couple of days later the father contacted my father and said that he (or his insurance) would not pay for this since it occured in a private parking lot, no police report had been filed, it was "no fault"?, and 4 weeks had already passed since the incident. This was extrememly upsetting as the only reason we didn't get a report was because my roomate pleaded that we didn't and now they decided they are not going to pay for the incident that was clearly thier fault. MY QUESTION is...does this seem like a legitimate reason as to why they or the insurance company should not have to pay or does this sound like a made up explanation? Also, what does it mean when he says "no fault"? Additionally, can they go through the father's insurance company since his son (who has his own policy and company) was driving the vehicle. Also, with the amount of time that has passed, can a police report still be filed? Any advice or legal information would be greatly appreciated.

A note..the way our insurance company works is that if we cannot get the money from the other party we have to pay a 250 dollar deductilble to get the car fixed...the other party would not even agree to pay this amount.