Before your sister reaches the Poly, she will approach the MK parking gate (they chg for MK parking). Your sister should tell them she is dining at 'OHana's and give her the PS # just in case. She should not pay for parking -- the charge is for MK parking.
At the Poly, there will be a security gate w/ a guard. She should tell security she is dining at the Poly. They do not charge, if you self park your car. Valet has a fee.