Did you repot both parts? They will probably live, just have some setbacks. Use peroxide first for rot then cinnamon. Peroxide works miracles on that black crap. Now that it is potted, it won't hurt to pour peroxide down into the medium to clean the roots, and it will make those roots or lack of much happier. Say it with me, what will be will be, and now a deep cleansing breath in through the nose, and out through the mouth.
Sometimes Grandma's don't understand lol. Give it good culture, and some peroxide again in 3 days, spray a little cinnamon spray when you water, and do a couple of growing dances for it. Yell at it if you have to, I am sending growing thoughts now
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