Not enough photos to make an honest determination. However, having stated that:
Purple one, if authentic, has a replacement fork that is NOT Colnago. The bike might have been crashed and it was replaced, then repainted along with the frame. Replacement decals such as the type shown are available. I can just make out the diamond-shaped brake bridge reinforcements in the third, but that's it. Even then, that's not necessarily exclusive to Colnagos. Need shots of the BB shell, lower head lug and seat lug arrangement to be sure.
Red one: no identifying marks to be seen. However, that fork also looks to be a replacement. Both forks, at a minimum, should have a clover or a clover in a large C cast into the shoulders of the crown.
DD