Peoplecode SQL not as expected

I have created this peoplecode method classDate(), in order to append a timestamp audit column from PSAUDIT

method getInfo2
  Local string &writeString;
  Local string &retTerm, &retDept, &retNum, &retSec, &retCourseTitle, &retInstructorName, &retContentType, &retISBN, &retTitle, &retEdition, &retAuthor, &retPublisher, &retStartDate, &retEndDate, &retCensusDate, &retClassCapacity, &retCourseID;
  Local SQL &sql = GetSQL(SQL.LC_BOOKLIST_SQL);
  
  While &sql.Fetch(&retTerm, &retDept, &retNum, &retSec, &retCourseTitle, &retInstructorName, &retContentType, &retISBN, &retTitle, &retEdition, &retAuthor, &retPublisher, &retStartDate, &retEndDate, &retCensusDate, &retClassCapacity, &retCourseID)
    
   %This.STRM = &retTerm;
   %This.CourseID = &retCourseID;
   %This.Section = &retSec;
   %This.classDate();
    
   &writeString = &retTerm | "," | &retDept | "," | &retNum | "," | &retSec | "," | &retCourseTitle | "," | &retInstructorName | "," | &retContentType | "," | &retISBN | "," | &retTitle | "," | &retEdition | "," | &retAuthor | "," | &retPublisher | "," | &retStartDate |