Augst defected to the Congressional Knights for different reasons; While his peers believe he had turned over to the darkside and betrayed the group of scientists he worked with, he was actually doing it so that he could try and steer the ARMs project back to it's original purpose of healing the planet from the countless wars that ravaged it. His reasons for working under the High Council are due to the fact that the scientists who took refuge in Ciel were refusing to do anything about how their work had been used for war, and decided on this even though he knew he would be thought ill of for it. It is highly likely that he is the reason that Brionac learned of the shelter's existence and was able to invade it, setting off the events of the game.