My hunch is that you should be looking for the marriage in Morgan co, Indiana. I am assuming that you found them on the 1870 cneus:
Hyndsdale, Jefferson, Morgan, In., p. 456a Franklin Benge, 39, farmer, Ky Almenda, 29, NC Gallant, 5 Marion, 3 Charles, 11 mo.
There are other Benges living in Morgan co.in 1870: Stephen, 19 Ellen, 16 They are living in Washington, Morgan co. in a Ballinger household. Both are born in Indiana. Samantha, 8, Also living in a Ballinger household in Hyndsdale.
On the 1860 census: Martinsville, Jefferson, Morgan, Indiana, p. 759 E. Goss, 26 Nancy, 19 S.F. Benge, 23, farm labor, Ky J. Ship___?, 21, Oh L.T. Benge, 29, Ky These Benges are living next door to a Ballinger family.
1850 census: Jefferson, Morgan, p. 82b William Bange, 30, ky Jane, 25, Ky Eliza, 8, In Elizabeth, 6 Nancy Jane, 4 stephen, 2 Iredel, 26, Ky
There are some Greens living in Morgan co. too in 1860, a few from NC. I couldn't locate Almeda however.
They still may have been married in Ky but I think you should start in Morgan co.