I'm so sorry to hear this, how awful. That had to have been so scary trying to break up a fight for that long. As Nebo has gotten older he has little tolerance for puppies, when he was younger he was great with them. With both Keva and Skya he bit them in the face a few times when they were bugging him...never an attack though, just bit them and they ran off crying. They learned soon enough to leave him alone when he's had enough, they get along great now. Zeus' tolerance for puppies may be long gone, this sounds way beyond just intolerance though. Neither bully breeds or malamutes are known to be great with other dogs, its possible he felt Titan was a threat even if Titan didn't start anything...just being a male could be enough. Best of luck to you with whatever choices you have to make, and again, very sorry you've had to go through this.