Once you have gone for a review your options are a bit limited now as you cant appeal in the normal sense. You will be challenging that the review process was unfair.
If you decide to request a review of your child’s test results it is important to note that the Appeals Panel will only be able to consider whether the review was carried out in a fair, consistent and objective way. Only if there is evidence that it was not fair, consistent and objective may the panel then consider any factors which you contend may have affected your child’s performance and any evidence you wish to present to support your claim that your child is of the required academic standard. If you go straight to appeal without a review of your child’s test results the panel will be able to consider these factors.
Some school have never upheld an appeal challenging the review while others have so you need to think about the schools you'll appeal for. You'll get better more informed responses in the appeal section of the forum. If you also use the search button at the top and search for something like "medway" or "review" in the appeal section and the medway section you'll find some old posts which maybe useful.
When did you write to the council about the incident? Was it immediately after or was it after you got the results? That would hold more weight if you advised them immediately after the incident.
Your school might have send adequate stuff but the problem with a Medway review is that it is very prescripitive and only 2% will go through. No less and no more unlike an appeal where they look at your extenuating circumstances.