Revealing mistake: When Truman is first discovered escaping on the boat, they go to a camera shot of his face. If you look at the water, the boat is not moving at all. They use a similar shot later in the scene after the storm. You can also tell the background is the same as the large wall that Truman crashes his boat into. (01:19:05 - 01:25:25)
Revealing mistake: If you look in Truman's car's mirror when he is backing up from the traffic jam, wires can be seen wrapped around his car.
Chosen answer: Because she would have revealed the truth to him. That's why she was removed from the set in the first place.
Phixius ★