He's still young. I think the crate is good. My dog wasn't allowed to stay alone in the house unsupervised until he was older. Make sure he doesn't wear a collar or have anything he could choke on in the crate. Is it possible for you or someone else to come home and let him out for a walk in the middle of the day to break up the crate time?
Chases Wolfgang Heinrich Von Ryan aka Wolfie born 12/20/09
Waiting for us at the bridge is Chases Chieftain aka Chiefy Left this earth and left a hole in our hearts July 2000