Hi Paul, There is a Random Acts Genealogical Kindness volunteer for King Co. who does public records (library) lookups. Go to www.raogk.org, read instructions, choose Washington, choose King Co. and look for Diane.
If that doesn't work out, contact the Washington State Library, , www.secstate.wa.gov/library/ask.aspx . They will look up the obit in the newspaper microfilm at no charge and reply with what they do or don't find. However, it does take about two weeks. Successful Searching!