You still do not want to eat them. From Little Falls Dam down being Lake Roosevelt is a popular fishery that does not have the concern that the upper river continues to have, warranted or not I do not know. The continued issues with the bottom of CDA Lake that feeds the river has really messed up the fishery with the exception of catch and release of course. Last I heard one a year for adults and none for children. With that said there seems to be no issues with the fish out of the Spokane arm of Lake Roosevelt or pretty much does not seem to be a issue below nine mile from what I understand. I will catch the crayfish and eat them as a adult with no worries as does many on the Spokane arm however I will not let my kids eat any of them.
It is really too bad as the river is a exceptional fishery with great potential.