I watched a episode of a similar show where the guy was in the Northern Canada wilderness and trying to make his way to a major road he knew was within 50k of where he was. It look the P***y 7 days. He even crossed a railroad track and decided to go through the wilderness instead of following it.
Hell, 50k is nothing. With a full canteen to start with I'd be done and looking for something fun to do my afternoon of day one.
If the brush was too bad I'd stay on the railroad track to the next town, outpost, whatever. You can make good time along the railroad track.
Being a marathon or ultramarathon runner in those situations makes it a whole new ball game.