I think the chief of a clan has to be the wyter priest, but I might be mistaken there.
Reading up on wyters, It says in the book that "these magical entities have become wyters through heroquests that bind the community together"
Would the actions of the PC's so far qualify? that is, performing "I fought WE won" and giving the salmonstone to Nilusa.
And if so, would that make the PC who gave Nilusa the stone the wyter priest (and thus probably chief of the new clan?)