well the other two were most likely following the good pups lead . just give them time and don't give up on them . i have seen and been guilty of using a lead dog too much and when you loose it you would think that it was the only good dog you owned . but you keep takeing the rest the pack out and they pick it up and go on with it . you still have puppys , just back up and start over with them you'll be fine .
x's 2, A new leader will eventually emerge, give em time, they are still young. I am guilty of relying on my best dog too often, I try to make it a point to leave him at home occasionally to make the others step it up a notch.