He would be killed. In "origin", I bring up a story as witnessed by my husband's grandfather that entailed a young male skinwalker who didn't want to live that life. He clearly said that if he left it, he would be killed. I think there is no question of the penalty for leaving. Also, he would risk being killed by the tribe itself. I can't remember the exact date but there was a "witch purge" not too long ago that resulted in the death of about 40 people. There would be no safe harbour for any that would want to leave.

Stephanie

In every man there is something wherein I may learn of him, and in that I am his pupil.--Ralph Waldo Emerson