I agree, that thing is going way too fast to be a contrail from a plane.
Look at the trees in the foreground early in the video. The speed they pass by matches the speed of the the “object.” I would guess an optical illusion as the helicopter is moving in the same direction. Almost appears to be some thing on the lens, though the object does appear to go behind the Empire State building. Hard to tell because the tower is very narrow at the point where the object passes by.