Funny end of the game

Olga Fedorovich stood absolutely chanceless against the winner of the Rapid tournament Ya Sai

Black has one piece more. And can choose between 23-29 with winning end of 25-30. But Chinese played 24-30??

After few moves we got this position:

Olga played 49.3-9

I'd prefer 19.42-38 and
a) 24-29, 38-33 and 37-31X
b) 24-30, 37-31 and 3x42 and 42-37X
c) 21-27, 3-9 without any difficulties

24-29 50.9-18 29-33 51.18-22 33-38 52.42x33 25-30

53.22-13?? 21-27?? (30-35, 13-18 21-27=) 54.13x36 30-34 55.36-22 34-40 56.33-29

2-0

The right (nice) win was 53.22-18 30-35 54.18-45! 21-27 55.37-32 27x29 56.45x18