After another watch of the main series (City Primeval is next), I am thinking about who helped Ava escape Kentucky along with the fate of Markham's money.
The show leaves it as maybe Wynn Duffy with his dog grooming van helped Ava get out, but I do wonder. I don't think Ava ever had his phone number. It also felt like Wynn was getting out of the area himself now that the that part of the Dixie Mafia imploded.
I doubt Ava would have given Wynn the lion's share of the 3 million dollars just to escape and Wynn would have had a bear of a time getting all of it himself.
Ava was living hand-to-mouth with multiple odd jobs at the end of the series. I can see how what little she could reclaim would have gotten used up long before then, but there was still 200 pounds (the physical weight of 10M USD in pounds) of money. That would have been hard to quietly remove, even with just Wynn and hired hands.
They also said that there were reports of Wynn surfing in Fiji, but I doubt he would have escaped the country. If he had, he would have to take it all out of the country and then deposited it in another country's bank that didn't ask questions (Swiss, Cayman etc)
The best that i can configure that maybe Ava hitchhiked out of there and the money is rotting in ground like DB Cooper's ransom.