@bbirdsong2 found a case where the answers submitted were incorrect and this was not caught (or at least reported) during grading. We need to check to make sure that it is being compared correctly with the correct answers.
I attempted the question multiple times using the same parameters and was never able to get this problem to occur again. I am going to close this and if it happens again we can see if we can pin point the issue.
@bbirdsong2 found a case where the answers submitted were incorrect and this was not caught (or at least reported) during grading. We need to check to make sure that it is being compared correctly with the correct answers.