CGFNS received your TOR and during their review, they found out that you are lacking in Microbiology, etc. Are you sure they told you that you lack "GRADE" not the Theoretical hours? Call them again and verify what you should do in this situation. Don't argue with them, they are the authority. Yes, some of their customer support agents are rude but not all. If you wait for their written instruction, you will be waiting (and wasting) a month to arrive in your door. Did you apply for Full course by course? Also check your TOR and verify if you have a grade in those subjects.
In my situation before, they asked for the theoretical hours of Microbiology not the grade because it is clearly there in the TOR. If you will notice, there is no microbiology entry in the Academic Verification form. So what they instructed me to do is to get a certification from the school (with school's letter head) that indicate the number of theoretical hours of Microbiology. Signed and sealed by the school. They already received the new certification when I got in touch with their written instruction.