I would leave it unwrapped...
Oops I didn't explain myself well. What I meant was that I covered the real cap with seran wrap then the fondant.
WOW! Fantastic looking cap, you did a great job on it. Once it sets up enough to hold it's shape without anything underneath it, I'd let that part get air to dry and setup too.
I made a purse handle today that has to be dry by tomorrow. I added tylose powder to my fondant and put it in the oven with only the light on. After about 3-4 hours it's dry! I'm amazed!!!