I cut more of the rotten root zone off (the lower piece), and I got the bad news. The fungus has made it up into the plant, traveling up the vascular bundle. (The reason the fungus travels up the vascular bundle may simply be that that's where the nutrients are concentrated. The fungus is a parasite eating the plant's food, and/or the plant) I was amazed that the plant's immune system has been checking the fungus somewhat. This plant is a goner, I think, but for the sake of the science, I decided to try the super glue treatment.