As far as I understand;
You only need to participate at the store to qualify for the prize (in all 5 sections, of course). It doesn't matter if you win, lose, or draw - you just need to have your name included.
However, if you wish to report the result (which only affect each Faction's global score, nothing more), then you need to play another game as Draw results cannot be reported.
Stores need only to collect /report names of players attending the event. The result submission is the (winning) player's job.
Not sure about #2 though.
Cheers,