I seriously doubt the Confederacy would have survived. If they would have won and seceded, it's likely they would have collapsed in the attempt to revert from a militaristic structure back into a civilian one, splintering into many different independent union-states and eventually being reunited into The Union proper. But the idea of the states' rights over The Federal Governemnt would have already been cemented. Contrary to popular belief, slavery was really an ancillary issue in regards to the Civil War, and it is my strong opinion that abolition and emancipation of slaves was an inevitability because it was ultimately a product of the change of culture, not the war. The war just catalyzed this cultural change and slavery was hardly the sole factor precipitating The Civil War.
They might have had more money but I would hazard a guess that the basis of their movie is informed by a ulterior and nefarious personal political agenda.