He was listed on October 31, 1864 as on detached service with Brigade Sharp Shooters. His regiment at the time was attached to the Consolidated Louisiana Brigade in Gordon’s Division. On February 25, 1865 he was listed present, temporarily transferred to Company A for payment. There, his record and that of his company and regiment ends.

As the regiment was paroled at Appomattox April 9, 1865, I would believe the obituary reporting he was killed on April 21 to be in error, perhaps he died on that date of wounds received earlier.

Before Petersburg means “in front of”, i.e., defending, a geographical reference, not a date.

He most likely is buried in an unmarked grave at the Blandford Cemetery, Petersburg. See;
http://civilwarhandbook.nfshost.com/cms/index.php?page=confederate-cemeteries-volume-1