Hi Chris, I first found Walter Matusewicz living in 1910 in Satsop, Chehalis Co., WA. He was b. Germany, abt. 1876, immigrated in 1902 and pending citizenship application, German-Polish, grader railroad and single.
A Walter Matusewicz died 13 April 1966 in Grays Harbor Co where he had lived per death cert #007753. Source: WA Death Index.
The Grays Harbor Gen. Soc., PO Box 867, Cosmopolis, WA 98537 might have additional info. Successful Hunting!