Complex sentence: He believes the "Demetrius" affair will cause more problems if the President doesn't come clean about the mission, and he hopes that as a Quorum member, Lee won't ignore the truth.
Split into simpler sentences: He believes the "Demetrius" affair will cause more problems if the President doesn't come clean about the mission. He ends saying he hopes, that as a Quorum member, Lee won't ignore the truth.