I too remember catching lots of true cod and hake while salmon fishing. I also remember catching them from the old Edmonds dock where my brother and I used to fish at night in the late 60's.
My dad used to have an old 30' Bristol Bay double ender sailboat that we would go on with him as long as he made sure we'd get a little fishing time. We used to catch lots of cod between Kingston & Edmonds.
One thing to remember (and I'm no expert) is that hake and true cod do look "similar". Also, there is a seperate fish called a Tom Cod which is a small version of the Pacific Cod, growing to maybe 12"-14" and can be mistaken for a young Pacific Cod. I remember one time catching dozens of them off our dad's sailbot in Quatermaster Harbor one evening and while bringing one up feeling a huge jerk on my rod, then back to normal. When that little Tom Cod came to the surface some kind of 8'+ shark loomed up from the deep following it. You never saw a couple of kids scramble for high ground faster than my brother and I did.