I actually thought the guy would have done much worse. Honestly it wasn't that bad for a rookie cb drafted in the 6th round in his first nfl game people.
Colman wasn't an illegal man downfield, he went out of bounds and came back in and was the first to touch the ball. Rookie or not, that was a horrible penalty. The net of the next punt gave Miami the ball in Jet territory, over 40 yards difference I believe.
What made that mistake worse was the fact that there 5 other Jets surrounding the ball and any of them could've touched it. There was no danger that a Dolphin was going to swoop in and pick it up. Boneheaded, selfish play.