Samantha:
Thanks for coming to the Mom's Panel.
The Cast Member you spoke to is correct. Disney's offer of the Dining Plan for free is extended to guests who purchase a minimum of a 3-night stay in a non-discounted room at a Disney resort along with at least a two-day, non-discounted Magic Your Way theme park ticket.
I'm assuming that you have purchased or are planning to purchase
Disney's Military Salute Ticket at its special savings cost of $169 plus tax. (It's tax-free if you purchase them at your MWR office.) Because this ticket is discounted, you would not be able to use it to qualify for the free dining offer. Keep in mind, though, that if you combine the Military Salute Ticket with Disney's discounted room rate for members of the military (details
here), you'll actually come out better, in my opinion, than scoring free dining.
Wishing y'all a magical vacation!
Whitney