Check out @defharo ‘s thread. He has a real wealth of knowledge.
And I just learned from him about proteolytic enzymes which the pineapple has. He mentioned overripe pineapple as well as green papaya and kiwi. I should throw some in my new batch because I do have some fatty fish.
In the past I’ve used fresh water fish with a moderate amount of oils. Never had the smell problem. Never used lake trout or salmon though.
Did you use enough molasses and sugar? Did you add some LAB or water from a natural ferment (sauerkraut,etc)?
I even threw some compost for added microbes this time - and because it was nearby. Leaf mold is good stuff too.