It does appear that Tryon is using some NXDN and what is known is posted on RRDB
Frequency License Type Tone Alpha Tag Description Mode Tag
155.07000 KLU261 RM Tryon FD Dsp Fire Dispatch NXDN Fire Dispatch
155.58000 KIQ247 RM Tryon PD Dsp Police Dispatch NXDN Law Dispatch
151.30250 WQKU332 BM 88.5 PL TryonFDOps1 Fire Ops Channel 1 FM Fire-Tac
154.05500 WQPJ990 BM 88.5 PL TryonFDOps3 Fire Ops Channel 3 FM Fire-Tac
158.82000 WQPJ990 BM 88.5 PL TryonFDOps2 Fire Ops Channel 2 FM Fire-Tac
Lacking other info, best thing to do is simply search while in the area... but that might take some time based on other posters in the above thread (activity sounds slower there than where I live!)