Here comes more analysis
19 Rfe1 Kf7
20 cxd5 (If Nxd5 the queen is pinned and the knight dies) fxg2 (honestly nothing matters anymore)
21 h5 (breaking the kingside) gxh5
22 Qxh7+ (If Ke8 then now the knight is pinned and d6, dxe7 etc is forced checkmate) Bg7
23 Qxh5+ Kg8 (Ke8 you lose as above, ...Kf8 24 Nc7 threatens the king/queen fork and hence wins the exchange on a8)
24

6 (Now since the king is kind of safe in g8, you have to make another threat. Since d6 is inadequately guarded, pushing the pawn and attacking the knight is very strong).
Now ...Nc8 to attack the pawn is bad because Re8+ forks the queen (the knight breaks coordination between queen and rook and makes the queen vulnerable), so Nc6 is the only other option.
24 ...Nc8
25 Nc7 (attacks the rook, but more importantly sets up for Re8+)
25 ...Ne5, putting the knight in the e-file protected by the bishop, thus avoiding impending disaster.
26 Nxa8 Qxa8
27

7 Nf3+ (Check protected by queen on a8, if not captured by the queen, will lead to checkmate)
28 Qxf3 Qxf3
29

8=Q+
It doesn't take an expert to see that two rooks are stronger than 1 bishop. 1-0