I think this much has already been answered by two "possibles" and one "plausible"
For example, did
Fingon fight at the Kinslaying? According to
The Annals of Aman and Christopher
Tolkien's constructed
Silmarillion (warning: mutliple f-sounds follow), the Feanoreans were succoured by Fingon with the foremost of
Fingolfin's host . . .
. . . so, presumably yes. In any case Fingon was there . . .
. . . but then there's a text in Tolkien's
Quenta Silmarillion, section 72, in which it it explicitly said that Fingon
"had no part in that deed" (which writing, in any case, preceded AAM). The point here is not about the external textual situation actually . . .
. . . but its illustration of folks who were arguably somewhere -- some-where where-some fight or battle took place -- that yet need not have taken part in a given battle.
Or something