I don't think its ever too old to start obedience. My mom will do obedience with the untrained shelter dogs are young adults and they pick up on stuff just fine
I don't know about how the two intact males relationship works...maybe its just cause they dont live together...or cause they are different breeds.
Why do they keep their dogs intact? eeeeerrrrrr lol do they think it's "manly" to not get them neutered and not take his "manhood" haha lol I always hate those kind of owners haha

or have they just not gotten around to it?