Hello Rob, never heard what the 2-mens names were. Just that they were members of the MO James Gang and both had been shot during and/or after while trying to make their get away from robing the San Miguel Bank abt. 29 DEC 1889.
Both men rode to AR area to friends houses to recover from their wounds and later married girls from these families (Fulkerson & Frazier) that nursed them back to health. Both men later used their wives surname instead of their own surname to make a clean break of being fugitives.
The Cunningham name is connected in here but cannot tell you if that was a surname of one of the men or not. Just it is listed as being related.