Could it be possible that this was put on the wall before absinthe was outlawed in 1912 (or since the ban was lifted in 2007). Maybe someone hallucinated Wyatt being there after drinking too much of the bar's namesake spirit. BTW, I love that place.
It's going to be hard to put him in New Orleans if you can't find him. Just as an interesting aside, the Old Absinthe Bar on Bourbon Street has a list of famous people who have been in the bar on its wall.... more