Is 'self-defense' for her and/or 'defense of others' for him starting to look more likely?  Maybe, maybe not.

There is no statute of limitations on Murder or any degree of Manslaughter in Oregon, so they can 'investigate' for years.

With a Felony parole hold, he isn't going to wander off too far, either.   And they have three years to file any new charge(s) out of this incident--even if he has to go back to the pen for whatever he did first.