Many thanks to @IllaGGJohnson who shared a photo that Keanu took with her kids in Brawley on twitter. She also tweeted that she got to shake Keanu’s hand. You see Keanu walking near a black car in the right panel.
Many thanks to Priscilla for also sharing the photos on her FB page and to L. who sent in the link. She has posted three photos (click through them). In the full photos, it appears that Keanu either drove his Porsche to the shoot or he rented one.
