Those Willapa Hatchery Chinook are very important to ocean fisheries. At one time, I think it was Koenings who approached Canada with an offer to really bump up Willapa production for them if Canada would go mark selective on Chinook. That way, we would further buffer the wild fish. Apparently, the fish survive well and contribute plus they are not super expensive to rear. Especially if you don't put in functional wiers and such.
Anyway, I suspect that WDFW is looking at the Really Big Picture and if this trap idea is all that keeps it from working then I am sure they'll go for it. It would allow buffering for wild fish in BC, even of not mark selective as there would be more hatchery fish, it would allow for bigger WA Coastal fisheries. All that is "missing" is local, especially freshwater, fisheries. Those are probably small potatoes as far as economics.