As per the rules:

"Entries must have a downloadable print-and-play file which is freely available for the duration of the jam and the voting period."

But afterwards, do whatever you want with the game! In my experience, with PWYW, you'll be lucky is 1% of downloaders chip in a dollar. With a paid product you're obviously going to reach fewer people, but if you want to make money from your game, is probably the better choice.