The attempt to conduct the defence without the knight is even more hopeless, e.g.:
A) 28.Rf2 Rg5 29.Qf1 Nh5 30.Nd3 Be3 31.f4 Rg4 32.Rg2 Ng3+;
B) 28.Qf2 Be3 29.Qxh4 Kg7;
C) 28.Rg1 Be3 29.Nc6 Rg5 30.Qxg5 Bxg5 31.Rxg5 Re3.

Black wins the a5-pawn, and has excellent chances to convert his extra material, with White having few chances of establishing an unbreachable fortress.

So as to exploit the weakened position of the black king, White needs to calculate the variations accurately. The dagger blow...

ends the game immediately.
In the game, White played the tame 23.Bh3, after which the battle flared up anew.

23...cxd4 24.Bd5+ Rxd5 (24...Kh8 25.Re7) 25.Re8.

24.Bd5+ Rxd5 25.Re7, allows the counter-combination on the theme of closing lines: 25...Ne2+! 26.Kf1 (26.R7xe2 Rd1; 26.R1xe2 Rd1+ 27.Kg2 Bc6+ 28.f3 Bxf3+) 26...Rf7 27.Rxf7 Kxf7 28.Qxh7+ Kf8, with a draw by perpetual check.

A longer winning line was 25.Rxf7 Ne2+ 26.Rxe2 Rd1+ 27.Bf1 Rxf1+ 28.Kxf1 Qd1+ 29.Re1 Bb5+ 30.Kg2 Qd5+ 31.Kg1 Qxf7 32.Qf4, penetrating with the queen into Black’s camp.

Two rooks on the seventh rank are a fearful strength. Instead of the tempting bishop retreat to e2, White finds a way to pose threats against the enemy king.

Now, the white rook gets the f6-square, and Black loses another pawn on the kingside.
More tenacious was 26...Bh8!, although after a line such as 27.Kxe2 a5 28.Rfe7 Re8 29.Rxe8+ Rxe8 30.Ra7 Bg7 31.Rxa5 Bf8 32.Ra7 Be7 33.Kf3 h5 34.Bb6!, with the idea of transferring the bishop via c7 to d6, White retains good winning chances.