Yes, technically NXDN would be either NBFM or SNFM using EIA terms which in current model Uniden terms is FM or NFM respectively.
Uniden does not support the true FM mode and has not for decades (if ever) - only SNFM, NBFM, and Broadcast FM (FMB).
(and I think used to support WFM which is what NTSC TV used)
Since this is the Uniden technical forum, I will tend to use Uniden terms and not EIA terms.
If you want a crossover table:
BW = EIA = Uniden
<=11.2 kHz = SNFM = NFM
11.3-16 kHz = NBFM = FM
16-40 kHz = FM = n/a
40-75 kHz = WFM = WFM
75-200 kHz = BCFM = FMB
NX96 is between the Uniden NFM and FM bandwidths (closer to NFM).
NX48 will likely work better on NFM since it is about half the NFM bandwidth.
Again, try both FM and NFM and see which one works better for you.
P.S. I believe 'ancient' FM used until the 60s (same for a few specialized uses) was 15 kHz deviation (40 kHz BW), not 25 kHz deviation.