Human
No explanation is necessary for the "human" faction. We know the general limits and tendencies of our fellow man. When Draco made contact with humanity, however, he saw something within us; something he knew the collective would want to harness. At first, he felt it would be necessary to be our guide in the fight against the Collective. After he saw just a few of our number in action, he reconsidered, letting the members of the Elma Resistance know that they did not need his help in a war to protect their home.
Certainly his expectations were formed based on his encounters with other alien species...Some trait we possess changed his tune. Our survival against the alien invaders may very well hinge on the resistance learning what this strength is and harnessing it to our fullest. Anything less may mean enslavement by the Collective!