What if the dog has a leash to scare the old man?

It is obvious that he is just trying to mislead you. But don't worry, it would be nice if there was a video. If there is no video, why should he blame you? Let him go to the police. Without a witness, the police can only judge that the evidence is insufficient. Even if he sues you, he has to go to the hospital for identification, otherwise the court will not accept it.

Satisfied, please adopt!