White plays and wins in 4 moves https://lichess.org/yLqwGPAk
- Re7 Rg5 2. Kxg5 Kg8 3. Kf6 Kh8 4. Re8#
The analysis board does checkmate in 5 moves
- Re4 Rg4 2. Bxg4 Kg8 3. Re8+ Kh7 4. Bf5+ Kh6 5. Rh8#
Source:
https://www.amazon.com/Chess-Puzzles-Advanced-Expert-Level/dp/B0917YQZP1