Yes, I have seen the herd in Dallas county twice with my own eyes. They are within city limits and are doing fine free range.
I have also seen free range axis near Okalla, just south of Copperas Cove.
Also seen some north and south of Abilene, but I think those were escapees and not sustaining free range.
However, I have never seen any real big antlers in the northern part of the state. Even on HF ranches, they seem to be smaller racked than those in the hill country - generally.