What stops cheating by officials (Score 0)

Who verifies that the replay by Hawkeye is really the shot just played. What's to stop the hawkeye operator just selecting the secret "give me the most similar replay(to the actual replay) that was out". Or in depending on which player is your paying customer. With the amount of computing power they have got, that would be easy. A whole match can turn on a couple of points. 5 all in the 5th set tie breaker. Wrong call(ie don't actually show what happened). All over