There's another solution with 1...Ng3.
Please post the url of the puzzle.
I agree, Ng3+ is equal to the solution accepted. Interestingly, Ng3+ is the move played in the game, where White resigns one move later. One wonders what more evidence is needed?
PS: Amazingly, Ng3+ is listed in the game annotation as a "mistake," even though computer eval is roughly even (less than one point difference) and the move wins the game on the spot.