The James W. Herndon who served in Co. G, 2nd Arkansas Infantry, applied for a Confederate pension from Saline County in 1901 [Pension No. 10793, approved August 28, 1901]. If you can get a copy of the pension application, that should help figure things out. If the man who is buried in Bethel Cemetery died before 1901, then he obviously isn't the 2nd Arkansas man, and the VA marker doesn't belong on that grave.