I am fairly sure that the information came from church records and will send you the links when I find those records (this is not my husband's Shroyer line and is sort of extraneous research that I do).
Of interest to you is this book that is available on Amazon.com. Looks like your ancestor was in a gun fight.
Product Description William Preston “Bill” Longley (1851-1878), though born into a strong Christian family, turned bad during Reconstruction in Texas, much like other young boys of that time, including the deadly John Wesley Hardin. He went on a murderous rampage over the last few years of his life, shotgunning Wilson Anderson in retribution for Anderson’s killing of a relative; killing George Thomas in McLennan County; and shooting William “Lou” Shroyer in a running gunfight. Longley even killed the Reverend William R. Lay while Lay was milking a cow. Once he was arrested in 1877, and subsequently sentenced to hang, his name became known statewide as an outlaw and a murderer. Through a series of “autobiographical” letters written from jail while awaiting the hangman, Longley created and reveled in his self-centered image as a fearsome, deadly gunfighter—the equal, if not the superior, of the vaunted Hardin. Declaring himself the “worst outlaw” in Texas, the story that he created became the basis for his historical legacy, unfortunately relied on and repeated over and over by previous biographers, but all wrong. In truth, Bill Longley was not the daring figure that he attempted to paint. Rick Miller’s thorough research shows that he was, instead, a braggart who exaggerated greatly his feats as a gunman. The murders that could be credited to him were generally nothing more than cowardly assassinations. Bloody Bill Longley was first published in a limited edition in 1996. Miller separates fact from fancy, attempting to prove or disprove Longley’s many claims of bloodshed. Since the time of the first edition, diligent research has located and identified the outlaw’s body, the absence of which was a longstanding myth in itself. This revised edition includes that part of the Longley story, as well as several new items of information that have since come to light.