there is no such thing as public DOMAIN content.....but those pictures were shot in a public place. ---big difference.
Battus owns the copyright to those images because he was the photographer and he doesn't need a release form to use them because the people in the photographs were at a public event where little privacy is expected.
If the girl was in her fenced backyard at her private pool and Battus peeked over the fence and took pictures, then he would not be able to use them because people on their own property behind a fence expect some privacy from photographers.
get it?