What you need to do is to find camera facing to the accident

cross street and offer to pay to get it, only police has the right to get the camera tapes but police would not ask unless death happened.

You also need get this kind of photo:

Find your phone calls history around that time showing you were not on the phone when accident happened.

Then you do not need worry about it, I got similar case but it was dismissed after 3 years of law suit, the only bad news is my insurance paid for my lose since I was unable to get video after one year showing I run green light.