White plays and wins in 3 moves https://lichess.org/stEpcMcC
- Nh5 Kg8 2. Nf6+ Kh8 3. g7#
The analysis board does checkmate in 5 moves
- Kf7 Ne6 2. g7+ Nxg7 3. hxg7+ Kh7 4. g8=Q+ Kh6 5. Qg6#
I was also thinking to escape the possible check with the horse, but I rather waited for that to happen.
Source:
This publication is in my collection "500 chess puzzles. Mate in 5. Advanced & Expert Level."