I don't think parole was ever going to be an option for Wayne's father and, as you say, probably a good thing he didn't get it.
Although he is a half breed, Wayne has always felt more Comanche than white. I think he wanted to spend time in their spiritual home and then bring Ethan there to make love on that land for the first time, before moving away.
Yes, a difficult childhood, especially for WQayne, is behind them and they can build a future together in California.
Thanks for all your comments @travlbug