I don't really have much on Dennis's other marriages, BUT, I do have a note that I took from the cemetery in Quitman.I was there looking for Dennis and Sarah's (first wife) graves and found one of the other wives with them:
E.C. Cargile 2 Apr 1853 - 6 Feb 1896
So, I'm guessing that E.C. is Emily.The date would be right since he married wife #3 in 1897.