You didn't mention what radio you are talking about, but there is no scanner by itself that will monitor NXDN.I ham assuming that this radio would pick up the NXDN freqs
It won't receive any frequencies that your scanner can't, but it will do NXDN just fine.
Receive freqs the scanner can't? NO....Decode NXDN signal that a scanner can't? Yes, but it won't do you much good around here. Everything NXDN in Sevier County Public Safety is on UHF and that radio is a VHF.