Black plays and wins in 4 moves https://lichess.org/vPJIYeiY/black
1... Nb4 2. c6 Nd2+ 3. Ka1 Kb3 4. c7 Nc2#
The analysis board does checkmate in 5 moves
1... Kd2 2. Ka1 Kc2 3. Ka2 Nb4+ 4. Ka1 Nd2 5. c6 Nb3#
Source:
https://www.amazon.com/Chess-Puzzles-Advanced-Expert-Level/dp/B0917YQZP1