Well, the main question they would ask is what makes her return back to Nepal after visiting US. A young recent graduate trying to visit US will definitely be seen as a potential immigrant. Her current job with estimated monthly income of 200-400 dollars is not a motivation to return back in the eyes of the CO. Success rate seems to be definitely low since student visa was already denied twice and they might feel that she is trying to go to US so badly. However u don't know unless u apply for it. So apply for the visa and good luck to her.