There is a lot of information missing in your report that could probably explain a lot.
First if you were not driving, does your policy cover other drivers who are not on your policy? Then who was at fault for the accident your driver or the other driver?
What does your policy state about a rental car? If it states you are entitled to one and they denied you, what was the reason they gave you?
Another big question is just how did you "loose" your deposit on your rental car? If you had to put a deposit down, that gets returned to you upon return of the car. The only reason they would keep the deposit is if you had additional charges that you did not pay for by another method.