Glad that you have the question resolved, however I would like to add my 2 cents. I am assuming that the WPA document is an index, and indexes can have mistakes. I have even found mistakes in the information from a cemetery office. Plus, I have seen errors on headstones; perhaps the stone was placed some time after the death and the wrong date was given or the carver made a mistake. Time may have worn the stone and it may have originally said 1844, but toady it reads 1841.
These are just a few thoughts as to why there could be a discrepancy.