Yaara, did you email the contact person on the Award description page - Sarah Diamond? She would be the best person to answer your question.
In my opinion, a cover sheet is just that: The title of the manuscript and all of your contact information. It says cover sheet, not cover letter, so I would interpret that as no need for a pitch/synopsis. But that's just me. I hope Sarah answers your question in time. And I would have it as the first page of the pdf file.