[Rune Son of Bjarne]

hmmm Doriath might have fallen anyways. . .probably would have actually, but we do not know.

The fact is that Hurin brings the Naulamir to Doriath and had he not done that. . .well everything could have happened. I know that you wanted to look aside from this, but I don't think it is possible to do so. You cannot just cut the most important part away and say "other than that there is nothing of importance".