As mentioned by Traffic_Is_Er-Was in post 324, I also think the black "shape" could be just shadow under a tree and the white "stripe" is a low wall painted white but time will tell.
As regards the pilot of the landing helicopter not looking left for traffic, is it possible he thought the departing heli took off from the same location in front of him with four helipads where he was going to land and the departing heli would be in front, moving to his right, to pass on his right side, separation would be increasing and it would not be a factor for his own landing?