Gradebook

I am using Moodle 1.9.11 and am having a difficult time with the T/F grades not populating properly to the grade book from a quiz.  The student is getting a correct markwhen I view the actual T/F quiz question (clicking on the 0/1 for the individual student), yet the grade book is marking it as 0/1  I've tried to regrade with no success.  I've gone into manually grade the question and it shows 0/1 also.  This is only happening on approximately 5 students out of the 25 in the class.  To my knowledge, this is not happening in any other courses.  This exam was imported via Examview.  I've attached screen shots for your viewing enjoyment.  Thanks