I'd say that 4 salt is exactly right. hooked in the gill plate is different that what hooked in the gills means. As far as the tongue goes I have caught many coho on spinners that were hooked in the tongue. Sometimes the hook goes into the little "slats" on the back of the tongue and when the hook hits the wrong spit back there the fish will bleed badly. Same goes for the gills. I have however caught lots and lots of fish that had healed eye wounds but were itherwise healthy so I think eye hooked fish can be safely released but thats just my opinion.