Brindle mixed breed guess

I got Chronos from a shelter here in Ft. Lupton Colorado, who rescues native reservation dogs (rez dogs). They aren't sure what mix he is. They first told me shepherd mix. When I saw him and asked more they said they honestly have no idea since it was basically a stray on the Rez. My best guess is it looks like he has some type of mountain cur or tree Tennessee Brindle. Maybe some lab. They estimated him to be 16 weeks and weighed him at 27 lbs I measured him today and from butt to chest he is 22 inches, from butt to nose about 29 inches. The top of his shoulders stand about 18-19 inches tall. He is either really active or super chill but I guess that's a pup for ya. Big deep bark for 4 months and these golden orange eyes that are bright. I attached a few pictures. Any help would be greatly appreciated. I was thinking of maybe getting a dna test at some point.