To be fair all the names like "Puyallup" and "Sequim" are because they were really, really bad at Anglicizing the native names way back when those places were "named" in English. If they were derived from the exact same native word now they'd spell them quite differently.
I mean, English speakers have this issue with huge numbers of Chinese words so it isn't too shocking that it happened with far less common native words.
pew-al-up
gosh dang native americans and their misplaced y's