Yes, there is video, but the only thing definitive on the video is that nothing on the video is definitive. It shows nothing.
Even Breitbart can't seem to make up its mind who was to blame.
There is a witness who knows Lewandowski, was standing right there, and confronted the goon after he did it. Video shows goon reaching in direction of Fields, but she is blocked from view. It happened, and is really sad that Trump and his lemmings have to lie about it.
Maybe you should call up Breitbart and tell them that. Here is what they had to say:
"Yet the available evidence from WPTV and ABC suggests that it was unlikely that Lewandowski was the person who caused her injuries."
"Given the similarity in appearance between Lewandowski and the security official, and given the fact that Lewandowski was walking on the other side of Trump from where Fields was at the time, the possibility of mistaken identity cannot be ruled out. Indeed, given Lewandowski’s adamant denials (coupled with statements inappropriately impugning Fields’s character), it is the likeliest explanation."
Seems they don't agree with you.
Source here read to the bottom of the article.