I take it you are returning via an Encore package you purchased, and you are using DC points to stay the remainder. When you purchased the package, it must have stated somewhere in the docs you signed whether it includes parking.
If your stay was purely on DC points, you would not pay for parking. I assume Encore packages also cover parking, so I'm thinking you just got the wrong person on the line. I would call again (making sure you got a different person) and start by
confirming if your stay under DC points includes parking. When they say it does, casually mention that part of the stay is under the package you mentioned and get confirmation that the whole stay will include parking. If they balk, state how confusing this is for you as a DC owner, no one mentioned it when you purchased the package, etc, etc, and ask to talk to a supervisor, or the person who sold you the package. They will probably not want to deal with you and may just say parking will be comped. Once you get a satisfactory answer, ask for an Email to be sent to you confirming that parking is covered. Note that they may end up moving you for the extra two nights, so it's possible they will make you pay for parking for as many as 5 nights, but I doubt they will put you through that.
Even as a weeks owner, my confirmation explicitly says that there will be a charge for parking - even though I have never paid a dime for parking. I have stated so many times how confusing and misleading this fee is on their confirmations.
Those who pay parking fee:
- ANYONE who uses valet parking (even owners)
- Those staying on an II exchange
- Those who booked as non-owners through some travel site (including Marriott)
Those who do NOT pay parking fee (one car max):
- Weeks owners staying at resort
- Those who booked using DC points
- Those staying as a GUEST of the owner on a reservation (this includes renters)
- Owners who extend their stay through Marriott (i.e purchasing an extra night). This was the case for us a couple of years ago when we were renting two weeks that had dissimilar arrival days so we purchased a night as a connector.
Not sure if you pay:
- Those staying on a package, but it should be explicitly stated in the papers you signed