I'm still not at all convinced that it's anywhere near the helicopter at any stage. Granted, it does fly right out of where the cab sits in the frame, but I think that's just pure coincidence.
Whatever it is will almost certainly have been elongated in the video because of the slow shutter speed being used on the camera (on account of it being dark above the stadium) and the speed of travel of the object (which if you assume it to have originated from the helicopter must be somewhere in the ballpark of 300mph!).