...or just making sure the Snow Queen don't come back?

Now that is sad. Black's position has become difficult, mainly owing to the immobility of the d7-knight. Probably 20...Nb8 has to be tried, hoping to redeploy at c6. But after 21.Qa5 Kd7 22.Rfb1 or 22.Qb5ch look interesting for White.

It's hard to see much wrong with this move (24.h4), blockading the advance of Black's h-pawn, protected from the knight's fine posting at f5. Once White gets in g3 and Kg2, it's hard to see how Black can mount an effective attack on the K-wing with the resources he has available.

25.g3 also works. 25...Qg4?? 26.Nh6 or even 26.f3 Qg6 27.Kh2 leaves Black wretchedly placed. After 25.g3, followed maybe by 26.Kg2, White's heavy pieces will be at liberty to begin operations on the other wing. E.g. White is threatening a swift finale by Ra5 ..., Rxc5 Nxc5, Qxc5 etc. If 25.g3 a5 26.Rfb1 threatens Rb5 or Rb7.

Black hasn't a lot of play available. White has an awful bind on the position whilst retaining enough flexibilty to undertake active operations. If Black were to resign in this position, I wouldn't blame him. It's hard to find any kind of plan that will give him counterplay.

Desperation. Objectively the move is bad - but that is a consequence of having no good moves available one imagines: a "zugzwang" position.

Rh7 also saves the rook.

Another idea was 33.Qe3 threatening a quick mate. If 33...Qc6 34.Ra5 or 33.Qb6 34.Rc8.

The drawback is that the Q is cut off from the Q-side. 34.Qe3 would just about end the game at once here.