they have a "Neutral" person.
Actually, they have a minimum of two people available to watch each box throughout the time when the election is open, the box is held in secure storage between close of poll and the count (with police on hand) and the boxes are opened with representatives of all protagonists witnessing the count. Imagine doing that
FOR EACH NATS SITE WHERE THERE ARE UNION MEMBERS FOR THE PERIOD WHEN THE BALLOT IS OPEN!
Give up the conspiracy theories - cockups DO happen!