The Moment of Truth (U.S. game show)

However, one contestant in the unaired second season (S02E09) did answer all 21 questions truthfully to win the top prize. The contestant was Melanie Williams, a member of a secretive polygamist group. Most of the questions centered around the secrets of polygamy and what took place in the group in which Williams was a member. For $500,000, Williams' final question was whether she believed her father had sexual relations as an adult with a minor. She said she felt he did, and the lie detector determined her truthful for the grand prize.

Question: has anyone ever won the moment of truth
Answer: yes