EWS category has been applied in very few states so it has not been applied in the entire india. So if you do not find any cutoff in DU then it clearly means that the EWS category has not been yet applied. I would suggest you to ask this abot the authority of the respective university they will tell you better about the reservation category. Also you can go to the collectorate office and you can ask about the applicabilty of this EWS category.