A similar thought experiment: If you could somehow pause the universe, create an exact duplicate, then press "play" on both at the same time, would they remain

A similar thought experiment: If you could somehow pause the universe, create an exact duplicate, then press "play" on both at the same time, would they remain in sync? Would their futures be the same? If so, it implies that any randomness we think exists is actually deterministic but too difficult for us to currently understand. If they diverge then randomness or free will do exist. But this doesn't explain what mechanism makes it possible.