The John Durham who died in 1926 was listed as a son of Joseph and Anna Durham. He was born near Martinsville, IN in 1842. Served in Co. G 25th Indiana Infantry during the war. In the Carr Township Cemetery index he is listed as being buried in the Lanning-Spur Cemetry. No marker on grave. I believe this is the same cemetery that Joseph Durham (died 1874) is in. The wives you have listed are correct.
The second John Durham died 1943 did marry a Anne Belle Waterberry. He was born in Rockcastle KY and came to Seymour at an early age.