Yes, my grandmother is still alive and was able to provide many of the clues in this search. This is her direct line.
John Schopf and Dorathea Pinneke married in Read township, Clayton County, Iowa, in 1876 and I have eyed that John Schapff as well. He is on other census listings and died in the local poorhouse (Clayton County Home, 18 Dec 1913.) To date, I can't find a record of a divorce between John and Dorathea. There are other Schoepf families in the local area and during the 1900 census he was living with the Matthew Schoepf family. Descendants of that family and I have been working to find out what connection there may be between these two men with the same surname. They reportedly came from Weissenstadt, Bavaria.
It's also interesting to note that Orva Wood and Katie Schopff married in Worth County, Iowa. Dorathea (Katie's mother) was living in South Dakota from no later than 1888, when Katie was 10 years old. Dorathea's siblings moved around to Kansas and then to Worth and Cerro Gordo counties between 1880 and 1900. The 1895 Iowa State Census shows Dorathea's father and brother living in Worth County. My grandmother recalls that her mother and her aunt "Gustie" (Augusta Below, daughter of Dorathea's husband number 2) would go to visit their cousins in Iowa regularly. I suppose that's where and how Katie met Orva Wood.
Thanks again for your interest and your help! I don't research much in Washington State and didn't know about their digital archives. I wish more states would follow suit!