According to Emil's thesis P. 42 figure 2.10 or P.48 figure 2.13 (b), 200 mrad of phase noise seems to degrade 15 dB of squeezing to almost 0 dB of squeezing. Our situation seems around 100 mrad of phase noise. Did you consider the effect of control bandwidth when you calculated rms phase noise? As you noted, it's better to measure the spectrum and integrate it within control bandwidth.