William Riley Allen was born in 1858 in Mich. All of his children(b. bet 1882-1900) and all but one of his grandchildren (most born bet 1900-1925), that I know of, have passed. So, I do not think Wm Riley Allen could have been Kevin's grandfather. When was Kevin born? Wm Riley did have a brother named John Franklin, born 1862 in Illinois. I do not know much about him.

Good luck! If you have found anything on other Allen families who came thru KS to AZ and NM, I'd love to hear. You never know when a connection can be made.