There were two newspapers published in Richardson County in 1866. The Southern Nebraskian in nearby Arago (1860-1872), and the Nebraska Register of Rulo (1864-1871).They were both published sporadically. They are available at the Nebraska Historical Society archives in Lincoln. The Arago paper is also available at the Falls City library. Unfortunately, the first known copy of the Rulo paper is dated July 5, 1866, a few months after the murder.
I found Emma's obituary in the Rulo column in the Falls City Journal of July 14, 1905. It was written by her son Edward.She was married to Thomas in 1842 and they had ten children.Nothing was given about her husband's death.She was buried in Rulo, but the name of the cemetery isn't given. (There are two)She has no tombstone and the cemetery records were destroyed by fire about 1935.
I did locate Eugene H. Johnson in the 1880 Rulo census living with his wife Nancy and four children. His occupation is given as Justice-of-the-peace. Johnson was born about 1827 in Vermont. He is listed in the cemetery records as dieing in Colorado, but no stone and no date.
I haven't found anything on Harnois, Scott, or Neuffman.
A possible motive for the murder:He was an ex-Union soldier in a pro Southern town soon after the Civil War. Many Missouri River towns in this area (NE/KS) were controlled by pro-slavery forces during the War.