Does anyone know of a marathon that happens in the pacific northwest, or anywhere near by?

There isn't one. We tried back in 2017 to hold "Northwest Speedfest" in Seattle and we did have the event, but the organizers wanted to make "the next one" better and it never happened. There's been constant cycles of "we'll have the information about the next event in a couple weeks" followed by six months of silence. The Discord server (which I can't even give an invite to, GG mods) is omeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeega dead ever since then. For literal years people have (seemingly) tried to reorganize but nothing has ever happened, and I doubt it ever will to be perfectly honest.