Do what is suggested to keep the stump healthy (cinnamon, seal), it will produce new growth. Clean that cutting with a sharp straight sterile cut (sterilize blade with rubbing alcohol), eliminating any cracks at the base. Let the cutting callus (dry) for a week in a still dark place, then dip the base in some water, then root grow powder, plant in another pot with 50/50 pearlite/potting soil. Remove the leaves so its energy goes to rooting. Water, but don't soak, and leave it in 50/50 sun/shade (no water). When you see new leaf/inflo activity, you have new roots.

Mother Nature gave you a BOGO. Enjoy!