I will agree that CP will be highly unlikely. Keep checking for an ADR even on the day you are in MK and want to go there. We've snagged a lot of day-of, hard-to-get ADR's (Chef Mickey's, BOG, Garden Grill, etc.)
Check for an ADR even before you ask about a walk up. A couple of trips ago, at the Wave (a whole different level ) we were turned away at breakfast. No walkups. We went out to the lobby and booked an ADR for 15 mins later. Walked back into the restaurant.