Pioneers of the San Juan Country by Sarah Platt Decker Chapter D.A.R., Durango, Colorado
Has a very detailed account of this story by the editor of the Delores Paper at the time.
In that account, Wilkinson was actually turned in by Stockton for the reward. The marshall in Durango and many locals were outraged by Stockton's self dealing. The Silverton Deputy Sheriff Jim Sullivan found a New Mexico warrant for Stockton confronted Stokton and shot him down. Stockton's end is described here. http://www.legendsofamerica.com/we-outlawgangslist5.html.
I highly recommend the reading of the Pioneers book and Searching the web for more info on Stockton as he was probably the primary Scoundrel in our local history. Stockton is reported to have a Barber in Animas City after the nervous barber cut him.