Hiruzen used the shadow clone jutsu after being put into the bringer of darkness genjutsu, that is why it affected him. If it even did affect his clones. How do you know that it did? He used his clones for one purpose and they went straight for the kages, so obviously they knew where they were.Please explain to me how it affected Hiruzen and both of his shadow clones at the same time then, with it being cast only once. What is canon the manga or data book? which do we go with when there is a conflict? I would say manga. You obviously say data book.
However, just for the sake of argument i'll simply say Hiruzen casts bringer 7 times.
I don't think the kages would be able to stop a meteor they can't see. I suppose they could potentially hear it, but I don't think it would matter.
Bringer of darkness is a short range genjutsu, unless Hashirama (not Hiruzen) were in close range to them then he would be unable to pull it off, and especially not be able to use it 7 times before he was killed. Unlike Edo Madara, Hashi cannot tank a dust release attack.