Here's another guess for you

[Maxy24]

This is Levi, he's sweet, he'll come say hi and then be on his merry way, he will pay attention to you if you try to get it but he is not super interested, he's not down in the dumps though, just has other priorities. He would chase the ball if you threw it but would not pick it up, I teased him with a tog toy and he mouthed at it and followed it with his head but did not really grab it or anything. He's sweet though, he'll lay near you, he was chilling with me in the first pic, and he is perfectly open to your petting and handling. He is attached to another dog and I didn't really see him interact with any dogs he was not already good with so I don't know how he generally is with strange dogs. His head is pretty massive, I liked to hold it lol. Save a Dog's guess isn't that bad but I definitely think they are missing a breed.

[Sweet72947]

Great Pyrenees comes to mind. Maybe with some GSD....

[colliewog]

That face looks like Rott/Golden to me ...