Amarak

Doctor Amorak was an associate of Gaius Baltar's who had survived the Cylon Holocaust, only to be presumed killed by their hand. (33)

Amorak alleged that he held information pertaining the downfall of Colonial civilization and had wanted to meet with the president, Laura Roslin, personally. (33) He feared that there were Cylon agents aboard the ship. According to Shelly Godfrey (alias for a duplicate Number Six), he entrusted a Colonial Defense Ministry encrypted disc to her, containing a doctored photograph of Baltar with an munitions device -- a device that would, in effect, take down the defense mainframe. (Six Degrees of Separation)

It is unknown whether or not Amorak was a Cylon agent; if he wasn't, then his fate (and information, were it real at all) was determined by Cylon hands.