Are they actually trunked or DMR? Appears as if McNairy County has several organizations on DMR VHF. You’re probably already aware of that already, but if they switched to Tennessee Advanced Communications Network that would be an actual trunked system. I didn’t see any listings for Medlink on TACN.
McNairy is on the complete opposite side of the state for me so I really wouldn’t know, but you’re likely to get an answer soon.
I’ll continue to search.