I see your point about saving money, but this would be way, way too much risk for me. It all depends on Disney's policy on unoccupied rooms, and I have no idea if the current policy is to cancel no-shows. I would absolutely not trust the phone CMs to give you the right answer on that, BTW.
They'll know that the room is not in use because housekeeping or security will be in there every day. I suspect they'll know that your magic bands aren't being used to open the door. Will they let the room sit unused for 11 days without cancelling? I don't know. If they do cancel, you'll lose all of your dining credits and probably your tickets too, as package reservations are non-refundable if not cancelled at least a day before your arrival.
It's a gamble - you risk almost $6000 to save $600. I'd be looking at other ways to save money, if it were me.
@KayKayJS 's suggestion is a good one, to get an AP and use that to get free parking. and meal discounts.