You never admit liability in traffic accidents...it's what insurance companies tell you.
You never apologise, that is an admission of guilt.
Maybe the man didn't know he hit anyone...maybe he diid know.
Maybe he hit someone, maybe he didn't.
That's not why the gun was drawn.
In the movies, when people feel physically threatened, they draw their guns, tell those threatening them to back off, then get in their cars and drive away.
"In the movies..." is movies. In the movies, people come back from the dead more often than in real life. People successfully kill dozens and hundreds of people who are trying to kill them. Using your "logic," there are superheroes flying around in the sky and aliens from space among us, not to mention a few vampires.
"Maybe the man didn't know he hit anyone..." has to be among the lamest things you have ever said. The man stopped the car.
But even if all he knew was there was a loud noise right behind him from somebody thumping on his car, he could see (once he looked) that he
at least almost hit her.
When that happens,
in civilized society, the driver apologizes. Why? Because the driver is at fault, with or without an admission of guilt, Bambi, and because he owes an apology. (It is true that according to the movies, if you hit somebody while backing up your car and you offer to take care of them in their pain, they may end up becoming an advisor to the president, but like I said, that's the movies!)
Your view of how the law works, how life works, and how people work is so broken it is a wonder you can breathe and eat and type.