Yeah, I can probably imagine there being a Confederate civil war if slavery doesn’t budge after the Congo Affair or the height of the Boll Weevil in the 1920s. By then, I think oil was discovered in Texas and Louisiana so they will definitely want to play into that, especially Texas where a Texan identity separate from the Confederacy will probably start to grow.
Then there’s the Upper South where even by 1860 slavery was merely tolerated and not practiced as if it were religion, or at least less so. Planter’s didn’t really control the governments of those states except maybe Virginia so there’s that. They were starting to industrialize IIRC and the more they industrialize, they are going to start realizing industrial slavery won’t last forever due to probable unrest from the majority poor white population.
If nothing nudges by the 1920s or 1930s, then I suspect the Upper South, and one with WV at that, and Texas will try to split and either try to go independent (more-so Texas) or rejoin the Union (more-so the Upper South). If get reabsorbed into the Union and the blacks engage in a Great Migration analogue then an already extremely racist North may become even more racist, all while leaving the black population of the remnant CSA in indefinite bondage. If Frederick Douglass was driven out of the North ITTL then things are going to be looking very dark all around.