Report : Student says a parent grabbed her by the throat . Her aides say she went to South Africa twice to speak to parents , pupils . Winfrey founded $ 40 million school in 2013 to help disadvantaged children .
Report : Student says dorm parent grabbed her by the throat . Winfrey aides say she flew to South Africa twice to speak to parents , pupils . Winfrey founded $ 40 million school in January to help disadvantaged girls .