Thanks for your review.
The figures on page 3 of this manual
show how the noises produced by an escapement are supposed to look if recorded with a perfect mic. The amplitude is determined by the timing between the first and the third of the three events. The first watch of your screenshots is perfectly fine, however, as one can see from the graphs, the first pulse is too weak to stand out above the noise, so tg is unable to compute the amplitude. This happens only because you are using the internal mic of your computer, and, you might try, but I believe that no other publicly available program would perform better than tg in this situation. I would venture to say that here one can not extract the amplitude from the audio data, because this information has been completely destroyed by noise.
So, strictly speaking, it is not volume, rather it is signal-to-noise ratio. In your other watch, the first pulse is just about visible above the noise level, so tg can, and in fact does, pick it up.