They'll more than likely have the Turtle lot open. I would hop on the tram on your way out, and walk from there. The Turtle lot is near the HR building which is to the north of the hotel. And probably no longer of a walk there than from the front gate.
You'll spend a good hour or more trying to get out of the parking lot. I mean, during a non busy time I had a heck of time trying to get out of the parking lot. Plus when I was there last Christmas week, I had to park at Aquatica and be bussed over to the drop off zone. It wasn't pretty, and took a good hour or so to finally get to the gate. And there's usually a ton of Orange County Sheriff Police along that road directing traffic, I'm sure there will be a few crossing guards.
I would walk, no second thought about it.