go to 1:58...and pause, look at the position
https://www.youtube.com/watch?v=rGEWzOv5Bc0
white plays ND4 preventing ND1 mate
and black rook cannot take the white knight cause of the white rook on D8

Um, Nd4 preventing Nd1 mate? What? How about Nd3 preventing Re1 mate?
Yes, it does stop the mate. Alas, it drops the knight to a pin.
go to 1:58...and pause, look at the position
https://www.youtube.com/watch?v=rGEWzOv5Bc0
white plays ND4 preventing ND1 mate
and black rook cannot take the white knight cause of the white rook on D8