They're all stat. sig. cept 21S-42P which is close enough. I didn't do 21S-64R because it's painfully obvious. (I also didn't do 21S-64P as you originally listed betting that I'll never see it in my lifetime or the next but I'd guess that to be a take also)
I did 21S-53S because I suspect that's the correct play also. Even if it isn't it's not like it's going to change your upcoming cube decision anyway. 21S-53P will clearly be a pass too.
The same goes for 21S-55, I rolled out the A play because I think it's right.

              
                   
 | is Player 2
score: 0 pip: 164 | | 1 point match | pip: 167 score: 0
is Player 1 | |
| XGID=-aa---E-C---dEa--c-e----B-:0:0:1:56:0:0:0:1:10 |
to play 56 |
| 1. | Rollout1 | 24/13 | eq: -0.016 |
| Player: Opponent: | 49.21% (G:13.30% B:1.55%) 50.79% (G:14.81% B:1.43%) | Conf: ± 0.004 (-0.020...-0.012) Duration: 2 hours 23 minutes |
|
| |
1 3888 Games rolled with Variance Reduction. Dice Seed: 1296 Moves and cube decisions: 3 ply
|

              
                   
 | is Player 2
score: 0 pip: 164 | | 1 point match | pip: 167 score: 0
is Player 1 | |
| XGID=-aa---E-C---dEa--c-e----B-:0:0:1:55:0:0:0:1:10 |
to play 55 |
| 1. | Rollout1 | 8/3(2) 6/1*(2) | eq: +0.021 |
| Player: Opponent: | 51.04% (G:25.82% B:2.45%) 48.96% (G:14.80% B:1.94%) | Conf: ± 0.008 (+0.013...+0.029) Duration: 1 hour 20 minutes |
|
| |
1 1296 Games rolled with Variance Reduction. Dice Seed: 1296 Moves and cube decisions: 3 ply
|

              
                   
 | is Player 2
score: 0 pip: 164 | | 1 point match | pip: 167 score: 0
is Player 1 | |
| XGID=-aa---E-C---dEa--c-e----B-:0:0:1:53:0:0:0:1:10 |
to play 53 |
| 1. | Rollout1 | 24/21 13/8 | eq: -0.037 |
| Player: Opponent: | 48.16% (G:15.36% B:1.84%) 51.84% (G:16.89% B:1.97%) | Conf: ± 0.008 (-0.045...-0.029) Duration: 1 hour 41 minutes |
|
| |
1 1296 Games rolled with Variance Reduction. Dice Seed: 1296 Moves and cube decisions: 3 ply
|

              
                   
 | is Player 2
score: 0 pip: 164 | | 1 point match | pip: 167 score: 0
is Player 1 | |
| XGID=-aa---E-C---dEa--c-e----B-:0:0:1:42:0:0:0:1:10 |
to play 42 |
| 1. | Rollout1 | 8/4 6/4 | eq: +0.005 |
| Player: Opponent: | 50.24% (G:17.30% B:2.25%) 49.76% (G:15.88% B:2.10%) | Conf: ± 0.006 (-0.001...+0.011) Duration: 1 hour 55 minutes |
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| |
1 2592 Games rolled with Variance Reduction. Dice Seed: 1296 Moves and cube decisions: 3 ply
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