Quite confused

Ok. I am still loving Visualwize. I am thinking how to achieve something similar by my own means but still haven’t come up with one complete idea. Somehow I think Chessbase manouvre search when you can have couple of moves in between something specific like mate and the current position could do. But how do I check if both players played best moves or not? Maybe this is not a problem as you try to work out the mate anyway and get to visualize while doing it.

Anyway here’s when it gets confusing:

White to move.

This is a position we are asked to visualize from couple moves back. This is a game between Jan Timman – Artur Yusupov 1987.

In actual game the move given as right answer actually worked. As Nxd4 Qxd4?? You see why the queen takes is a blunder? It’s quite typical ladder. You make the “ladder” of queen and rook fall down with fork - Re8+! After this it’s quite simple. If Rdxe8 Qxd4 and if Kh7 Qxd4 Rxd4 we win the second rook on a8.

But. What if Nxd4 Rxd4!? isn’t this just equal? What am I missing?

Edit: Got a quick response from Louis Holtzhausen that confirmed that Rxd4 just had slipped his attention and he promised to correct the problem and send to link for that one to me. Soooo. Now I feel pretty good about spotting that one!