Need help tracking down a soldier from New Orleans who served in the CSA, First Company, Washington Battalion Artillery: Robert H. Alsobrook, son of New Orleans merchant Henry R. Alsobrook and Lavinia Moore.

Question: Online there are TWO burial spots listed for him - anyone know how this can be? Where is he actually buried???
1. Orleans Parish, Metairie Cemetery, DOD 21 Feb 1891
2. Orleans Parish, St. Louis Cemetery #1, (just a notation with this burial, no DOD)

Question: We have been unable to find any trace of him after the war; he seems to have disappeared into thin air. Since his family was a fairly well to do family, it seems unlikely that he was homeless after the war, and based on the cemetery transcriptions above, seems to have gone home to New Orleans after the war - at least it seems he died there. Is there any information available that perhaps talks about the men of Washington Artillery and what happened to them after the war? Did they have reunions, share stories, etc.? Maybe we could find a clue there. We also would like to find out if he married and had kids.

Any suggestions/help greatly appreciated. Thanks!