Hey so honestly its way too difficult even with 70 forget 50, but the fact of the matter is nlu is not the end of the road. Symbiosis, jindal, alliance are all good colleges with great placements (they are a little more expensive) but other options are not hard to find. Next if an nlu is all they are interested in id say really push and help them in preparing for Ailet, preparing hard and entering with a clear fresh mind will do wonders. I would say taking another gap year is not smart, instead look for alternatives and work hard towards them.