Is there a way to exclude certain keywords from a regexp_match statement in Tableau?

I am trying edit the calculation field and pull in filenames that contain the string 'NDA.' However, filenames that contain 'STANDARD' also get pulled in error. Is there a way to do this in Tableau? I have tried the follow but it becomes too restrictive and the majority of files I'd expect to pull don't get pulled no more.

 IF  REGEXP_MATCH(UPPER([Name]),'_NDA|NDA_|_NDA_|NDA<>STANDARD')THEN "Nondisclosure Agreement"