Jim, you were close and it may well have been mistaken on Mayo's part. The name that I have listed on that roster is Eli McDaniel or Ely McDaniel. He was definitely in Co. F, 8th La. I could not find any Eli M. Daniel in any unit so feel pretty certain this is your man. Here is what I have on him:
McDaniel, Eli, Private

Eli McDaniel was a 16-year-old farmer (born 1847 which sounds more like age 15) in St. Landry parish when he left parents, Aguala McDaniel and Celise Fontenot, to be recruited to enlist in the 8th Regiment at Opelousas on March 30th, 1862. Eli was present until captured at Gettysburg on July 2nd, 1863 and sent to Ft. Delaware. He was paroled in 1863 but not released on Oath of Allegiance until June 9th, 1865. For some reason his comrades stated that he was "destitute of personal pride". He came home and married Azelie Gonor on May 10th, 1871 in Opelousas. Eli died of pneumonia in Lafayette, LA on Feb. 11th, 1901 and is buried there in St. John Cemetery. His name is also spelled as Ely, Elie or simply Eli as is listed on his headstone.

That "destitute of personal pride" could mean many things that I would not even begin to speculate upon. It may be better we don't know.