Puzzle 58783 is faulty

On Puzzle 58783 (link: lichess.org/training/58783), I spent a while to find the move Qf6+ instead of simply capturing the Knight, which failed the puzzle and took a chunk of points off my rating. I checked with Stockfish 6 to verify the solution. At first, it indeed wants to capture the Knight, but once you input Qf6+ its evaluation rises, and lo and behold, it evaluates Qf6+ as a substantially stronger move. Therefore, I would like to report this puzzle as faulty.

This seems to be a common occurence with non mating problems, only the top move is accepted, even if you find another easy win.

Yes, but in this case the top move (Qf6+, which I would say is more difficult to find than simply capturing the Knight) is actually given as the wrong answer! I think the Lichess staff should correct it.