I think I also found the driver:
"Flash (1934) the MGM dog (a Hollywood star in his own rights) With the box office magic generated at Warner Bothers by Rin Tin Tin, other film studios were keen to find their own lucrative dog heroes. Flash was a German Shepherd, who appeared as a puppy in HIS MASTER’S VOICE in 1925, followed by another eight films for MGM, before honourably retiring in 1938."
He could also drive motorcycles