It specifically states on the website that DVC reservations get the room credit as well. If you go to the bottom of the page here:
https://www.disneyaulani.com/pool-refurbishment/ and expand the FAQ, it states:
Q. Are you providing any special offers during the pool refurbishment time period?
A. All Guests and Disney Vacation Club Members visiting Aulani Resort for stays between August 19 and December 17, 2019 will receive a $50 Resort credit per room, per night* that can be used toward any of our offerings—including dining, merchandise, spa and excursions. This Resort credit is valid for any length of stay and will be redeemed at check-in.
*This offer is valid for Guests staying between August 19 and December 17, 2019. Resort credit may not be redeemed for cash, refunded, transferred or applied towards room rate and will expire at 11:59 PM on departure date. Credit offer not available to those Guests booking on a Cast rate, Cast Friends and Family rate, RSR rate, Industry Courtesy rate, and Cost Recovery rates. Advance reservations required.