I think it's now pretty clear (see image below, taken from the website of the two guys that compiled it: http://tommentonenlacuadra.blogspot.com/2020/02/va-acetates-vols-1-3-compiled-by-brayan.html?m=1).
Here's the comps uploaded on YT.
When I uploaded it I checked if there was a difference between the two folders and I remember the size was the same.
However, luckily the error has been found.