I did some spectral analysis again, with the same SoX configuration as in
this post. Turns out that Square-Enix is beginning to improve.
Find the
images here.
As one can see there is lots of spectral energy in the domain between 24kHz and 48kHz (the sampling rate of the LPCM track is 96kHz). So this looks like a genuine transfer from the recording master, and not just some upsampling job.
Still one can see some issue which is either due to recording to to resampling (constant energy at around 46kHz).
Good job nonetheless, much better than the previous releases. Haven't looked into the dynamic range yet though...