Don’t know about Prime4, but being internally like an X18x0 mixer, I can elaborate a bit.
Recording #2 is exactly like on an X18x0 mixer when SC’s connected and recorded digitally. It is linked to the source material btw. Nearly all tracks for the last decades have a hard limit for maximum loudness. When all knobs are at center position, the mixer tries to produce a bit-perfect digital signal (squared waveform as per source material). Only during blending the mixer applies a non-limiting “dynamic”.
My explanation for recording #1 is the result of above explanation that probably a filter/EQ/FX was active anywhere on Prime4 (so non-centered).
So, it is really the other way around. The compression/limiting you see is in reality the untouched/unprocessed source signal coming through the mixer bit-by-bit.
Feel free to test/check this. Would like to know more on this. I presume all was recorded internally on the drive as the unit does not have a digital out.
See a mix of mine on the X1800. You’ll see exactly when I blend and the mixer goes into dynamic processing mode 
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I just apply the same maximizer (as they do to our music, for the last decades) after recording the mix 
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