No- not guaranteed. NMF status is only one (small) part of the application. Your GPA, SAT/ACT scores, and EC's are all important factors in acceptance/rejection. In addition, your essays and rec's tell a story about who you are. Some NMF meet all the criteria of USC and others won't. Many NMF feel qualified and are surprised when they are rejected-- remember, USC reviews whole applications to make decisions.
All who ARE admitted, though, will get the NMF Presidential scholarship (parents have confirmed this again for this year-- see other numerous threads).