The NXDN frequencies for the county (Maury), as well as the city of Columbia are licensed as conventional, not as trunked systems. That does not guarantee that they are not using a trunked system, but that is not the way they are licensed.
Also, on the database page, a number of the entries are incomplete:
View attachment 115443
These are tagged as NXDN, but no indication of what RAN (if any) is being used.
Look at some of the Columbia listings:
View attachment 115444
An RAN is listed for two of them, but blank for the others.
There is likely a talkgroup assigned, but it is not listed either. It's also possible that they simply use deither a default TGID of, say,
1, or maybe none.
If I were trying to figure this one out, I would program these into a One Frequency Trunked system. Each frequency as a separate site, with the RAN field set as Search. I would set the system as ID Search, and recommend creating a department with a dummy TGID as a placekeeper. You can create a site for each frequency, labeling it with the alpha tag shown on the database page (i.e MCSO-DISP1 D). Set the scanner to record all transmissions. Let it run for a while, to get a good selection of transmissions received.
Once you've let it run, put the scanner in mass storage mode, like you were going to update programming. You can use the Universal Scanner Audio Player to review your recordings. It will display any information from the recordings as to RAN and talkgroups (if any). I would copy the audio files to your PC, and read them off the pc, but you can also listen to them while still stored on the scanner.