I wouldn't worry too much about what to do if you have to take your daughter out. If you have to leave they will pack the food up for you no problem.
I'll stay out of the giving people advice on what ot do with their kids on vacation business. I will say this though......some of our best meals have been late seatings where our boys (4 and 6 who fall asleep by 8:00 or 8:30 even on vacation and in the MK) sleep soundly in the stroller next to our table. So, depending on the child, whom the parents know best, later could be just as good (or better) than earlier.