Check out this article about the Pipestone Black Sox of Minnesota, an independent African-American team that played in 1926.  The big story here is that the authors believe that Dave Brown, the brilliant pitcher who went on the lam after killing a man in a bar fight in 1925, played for the Black Sox under the name “Lefty Wilson.”  They also identify a couple of other black big leaguers on the team, including “Lightner.”  I’m not sure whether they have independent evidence that this Lightner was the same guy who pitched with the Monarchs in 1920, or if they just looked up his name in Riley’s encyclopedia (which they cite).