Hard to say, its likely that these are union shops that produce parts for other manufacturers as well.
From the names it sounds as those the 3 shops were Japanese, Japanese/American owned. They provided two of the parts that have been blamed. I heard elsewhere that it was American parts that had the difficulties, not the ones made in Japan. Perhaps the FBI was seizing parts before possible evidence disappeared. Could there have been graft (inferior production) or Yakuza involvement? Or is it in fact a union sponsored ploy? Time will tell.