That is new to me too. I didn't read the entire article though. I wonder what the source of this story is.
As for Southerners fearing the black population being "turned loose" in their midst I believe they probably did feel that way. Suppose today somebody dropped off several million people with no education in our midst. I bet we would all be concerned.
Maybe if the northern states had made an effort to assist in what to do with these freedmen to help them compete in society things may have been different but the truth is the northern populace didn't even want to compete for jobs with the blacks, much less start sharing land and other property.