FF02,
Release mortality is the fraction of fish that are required to be released and subsequently die. For non-tribal commercial fishers with a standard gill net it is typically 56% of released fish. For recreational fishers, it is 10% in fresh water and 14% in marine water. Tribal fishers do not release anything so it does not apply to them. These two numbers have nothing to do with this thread which is about drop out, drop off and pinnipeds.

Recreational anglers also get charged with drop off which is expressed as 5% of the fish you punched. Suppose you lose 50% of your hook-ups and 10% of them die or fail to spawn. Presto, a 5% loss. Your retained fish counts as 1.05 harvested fish. Non-tribal commercial fishers are charged with a net drop out of 2% for coho and 3% for chinook. Harvest is counted as 102% or 103% of the expected fish in the boat. I can easily visualize this as the fish that fall out of a net as it rises from the water to the boat deck. It is unlikely to represent any pinniped harvest which I think would be about ten times this amount. As near as I can determine the tribal harvest model has no drop out for any reason. This significantly understates their harvest mortality and their share of the harvestable fish.
My comments come with the caveat that I have no current or former connection to WDFW. I am simply using my knowledge of arithmetic to examine how things are manipulated in the harvest models. Sometimes it is a leap to say how they got the way they are.