Current position (for you top-of-the-pagers).
So my position is a little bit worse than I had thought. I think it's farewell to dreams of making something happen, and to put my effort into safely guiding this to its conclusion without getting myself into any more trouble. Some fun puzzles:
After 27...Rd8?? White to play and win.
After 27...Re8, White captures on d5, reaching the position below. What's the best move?
After 27...a5, the same tactic shows up one move earlier:
Note that the above (spoilered) tactic works even if Black just passes the move. To be honest, I don't see a way for White to force a win in those lines, and his own king is not so safe with the open c,h-files...but let's defer that for the moment.
So it's clear that Black doesn't have a lot of options, as Rxd5 is a real threat.
If Black wants to avoid the draw, then a5 is hard to play, after 28.Rb5 Qc6 29.Rc5 Qe8 is the only move. I'm a little concerned with Black giving up this much space. It's only going to get harder to unwind. And, of course, a5 still requires analysis of the Rxd5 exchange "sacrifice" endgame.
If 27...Rc8 28.Qc2 Rxc5 29.dxc5 with the idea of Bd6 seems pretty unpleasant for Black. Surely, this is to be avoided.
So the safe 27...h6 seems to be the most promising. Now 28.Rxd5? Qxd5 29. Bxf6 hxg5 is nothing, so White needs to retreat the knight. Ne4 seems most sensible, and after Nxe4, g7 might be troublesome, so I think Nfd7 might be best. Yes, Nfd7-b6-d7-f6-d7 will be 15% of my moves. I'm not thrilled about it either. BUT when the rook moves, Black can play Qb5...and bask in that for a move or two until White plays Nd6.
So I have a little more thinking to do -- mostly about the "Black passes, Rxd5" lines (after a5, I guess...but Re8 and I guess Qa7 are alternatives...). White, of course, might play something other than Rxd5, and the outcome of the Rxd5 variations is itself unclear to me. I'm guessing that these are fine for White, but I need to just hack away at those lines some more. The queen+knight generally do work well together (at least that's the conventional wisdom), so it's a question of whether the knight can find a decent outpost and whether White's king is safe enough.
Postscript: I know I mentioned b3 in the previous post. Although it is a creative solution to those Rxd5 lines (bxa2! will be timely) White can always play axb3 first, in which case I don't see what's gained.