Hi phyl g - Your message hadn't posted yet when I began my reply. I also concluded that Donald might be hiding under the nickname "Bud."
Original Poster: You ask only about Donald, not about his wife. Are we looking for the two of them as a couple?
I think Donald's sister Vergene Rutz Hayter died 24 Jan 2006 (not 2012); buried in Enterprise.
Donald's father Arnold Rutz who died 24 March 1976 married twice - so you might try the obit of the second wife. Married 1st in 1917 to Erma Heller d 23 June 1955 Married 2nd in 1956 to Ida Comer (Source: Find-a-grave)
As a long shot you might check the obits for Donald's grandparents as well. Donald's father Arnold was the son of Henry Rutz and Emaline Spenner. Per Find-a-Grave Henry and Emmaline moved to Texas in 1927.
Henry Rutz died 01 March 1955 in Booker, Lipscomb, Texas Emmaline Katherine Spenner Rutz died 30 Jan 1950 in Booker. (Source: Find-a-grave)
I haven't looked up Donald's maternal grandparents info.
I guess we're all saying this is the procedure: 1) Identify the whereabouts of Donald's siblings and their spouses and children and contact them. 2) If they have died, check their obits to see if he is mentioned.
One could go on finding family information - but I suspect you already know a lot of it.