Are wild coho expected to be in the area in any abundance? I'm guessing not since Willapa has traditionally been managed as a hatchery wipe out fishery with little to no regard to wild salmon.
I think the gillnet boat will have to fish very tight to the mouth of the Nemah, rather than the broader limit of Needle Point to Ramsey Point if they actually intend to avoid wild Naselle chinook. I don't have a WB chart, but chinook would be expected to hug the edge of the thalweg channel which could lie inside the specified fishing boundary line.
Then there is this over-riding thought: WDFW needs to come to terms with a long-term management outlook for WB. Having it both ways - hatchery wipe out and wild stock preservation - is mutually exclusive. Keep with tradition, managing for hatchery stocks and end up with ESA listings, or actually manage for wild stocks, where hatchery fish supplement harvestable numbers, rather than replace wild fish. Pretending they can split the baby and have it survive is delusional.