Yes, they did go NXDN digital. It took me a while to realize they had gone digital, since I don't listen to them that often. If you listen to 155.7375 in CSQ mode, you'll hear white noise that sounds like rushing water. That's NXDN digital.
I did run DSD+ on them and its coming back as NXDN 4800. It appears they may be encrypted, but I don't know if i'm getting a good signal enough signal to demodulate or not.