White plays and wins in 3 moves https://lichess.org/t37OrvcU
- g6 Kg8 2. h7+ Kh8 3. g7#
The analysis board does checkmate in 5 moves
- g6 Bc2 2. h7 Bxg6 3. Kxg6 a4 4. Kh6 a3 5. Ng6#
Source:
This publication is in my collection "500 chess puzzles. Mate in 5. Advanced & Expert Level."