What I don't understand is... how did the box not
work? We saw it work. It clearly connected with their future, and we clearly saw the cargo being transported through the wormhole. We even saw a minor black hole effect after the antimatter was injected into it.
So... how did the Observer sabotage Peter's efforts? I just don't get it. Especially since there was only one option that would work and the other three would cause them to go up in ash.