Q. Do I report all five month's rent or just the August/September rent?
A. All five months. It's not relevant (for the state renters credit) where the money came from, if you are otherwise qualified.
A separate question is: Do you need to report the 529 plan distribution? For the answer to that question, we need more info. Mainly, were you a half time or more student during Oct & Nov? What other qualified educational expenses (QEE) do you have and how do you plan to report the QEE (e.g. claim a tuition credit)? What is the school's allowance for attendance for off campus "room" (essentially what to on campus students pay for a dorm room). Off campus Room and Board are qualified expenses, for a 529 distribution. But, you are limited to your actual cost or the school's "allowance for attendance", whichever is less.