Appears you'll have to call Kaufman County Clerk for that info? http://www.sos.state.tx.us/elections/voter/cclerks.shtml#M
She was Mary Genia Dorrill/Dorrell daughter of George N. Dorrill and Barbara Walton from Leake, MS. Unfortunately, another N.M. Guynes wed Angie Taylor, 25 Jun 1901 in Hardin, TX per https://familysearch.org/
Don't know the length of that union but he ended with Christina Lucinda "Tennie" Kerr Guynes. Ancestry.com incorrectly cross-referencing the two families.