If that marriage I found is the right one, I believe that S S Vanwinkle was Simon Vanwinkle. Here he is with his parents in 1870 IN. In 1880 Ezekiel and Elizabeth Vanwinkle are in Oregon Co, MO, but there's no sign of Simon. There is a marriage record for him as S S Vanwinkle from 1880 there in Oregon Co.
1870 United States Federal Census Pigeon, Warrick, Indiana Ezekiel Vanwinkle 43 w m farmer IN Elizabeth Vanwinkle 40 f w IN Hiram Vanwinkle 17 m w IN Siman Vanwinkle 15 m w IN Jasper Vanwinkle 13 m w IN Benjamin F Vanwinkle 9 m w IN Amos O Vanwinkle 4 m w IN King D Vanwinkle 1/12 m w IN
And here's the M M I McCluskey with her parents in 1880. Looking at the few census listings with her as a child she is always called Martha, so this may not be your Isabel.
1880 United States Federal Census Pike Creek, Shannon, Missouri Isaac Mc Clusky 63 w m farmer SC IRE IRE Martha A. Mc Clusky 57 w f wife AL GA KY Charity R. Mc Clusky 28 w f dau MI SC AL Martha H. Mc Clusky 22 w f dau MO SC AL Nancy E. Mc Clusky 18 w f dau MO SC AL Lucinda C. Mc Clusky 17 w f dau MO SC AL Harriet J. Mc Clusky 15 w f dau AR SC AL Isaac J. H. Mc Clusky 13 w m son AR SC AL
I found Isaac Vanwinkle and Martha Banks' marriage record on familysearch.org
Arkansas, Marriages, 1837-1944 groom's name: I. A. Vanwinkle groom's birth date: 1884 groom's birthplace: groom's age: 21 bride's name: Martha Banks bride's birth date: 1889 bride's birthplace: bride's age: 16 marriage date: 29 Oct 1905 marriage place: Randolph, Arkansas