Complex sentence: In 1887, one other eye-witness, David Whitmer, recollected that the event occurred in his father's home in Fayette, however, years earlier, in 1875, Whitmer had already told a reporter that the event occurred in Manchester.
Split into simpler sentences: In 1887, one other eye-witness, David Whitmer, also recollected that the event occurred in his father's home in Fayette. However, years earlier, in 1875, Whitmer had already told a reporter that the event occurred in Manchester.