Cal did not cost the team the game; that's nonsense.
But there is room for criticism. As others have said, the switching every screen has to stop. For someone who professes to not have a style and to coach to the players he has, Cal is incredibly stubborn in this area. You can play that way if you have an Anthony Davis, Willie Cauley-Stein, Nerlens Noel, or even Terrence Jones - big guys who move their feet like guards and can close space even when they get blown by. There is nobody on this team who fits that description - nobody even close, really. Bam is a "step slow" in everything he does.
The other thing is there is no explanation for the lineup we had on the floor on the last possession. We had to have a three, and there was not enough time for a shot, offensive rebound, and another three. So why was Bam on the floor? It's not like they even used him to set a screen. You had to have Mulder on the floor at that point. Is he the savior? Of course not. Would he have made the shot? Who knows. But he has to be on the floor in a 3-point game with 8 seconds left. If he's not on the floor in that situation, then I'm not sure why he's there.