Wow, your 4Runner did an amazing job in protecting you and your family!
Sure, it sucks royally, but you can always get another truck.
My husband just got side swiped by a person in a Uhaul and we had to actually go to the police station to get a different report that stated it was the other person's fault. So if the cop gave you a report and it didn't state who was at fault, you just have to go to the police station and get the correct one. Not certain if that is true where you are.... We are in SC, and apparently that has become the standard thing here.
Also, my 4th gen (2007 sport edition) hit a year and a half ago while in a parking spot, and I left the insurance adjuster a note attached to the wiper blades in a plastic bag about all of the mods and maintenance I did on my vehicle and she valued it at $13,500 with over 170k miles. So if you have mods and recent maintenance, you have to fight for what they will pay you! Best of luck.
You're lucky a cop was by you too... that should be plenty enough evidence to get their insurance to pay for a rental for you and give you the value of your 4Runner. You could also get a dealer to give you a quote on what they would sell it for used, in case the insurance adjuster low balls you.
Best thing still... you and your family are OK!!