Where else did you find it to be out of sync after correcting the 120ms at 20:12?
As far as I can tell by looking at the waveforms, the corrected audio remains in sync with the fake mono track from the BD right up to the end. Of course there are occasional spots where a sound effect or some dialogue is just a few milliseconds out one way or the other between tracks, but that's expected with two completely different audio mixes.