The international newcomers secured the sixth and final berth, by default, after Fiji, Samoa and Tonga all withdrew from last month's Pacific qualifying tournament due to a lack of playing numbers.
The Cook Islands have been drawn in Pool A, alongside defending champions Australia and England, who finished third at the 2013 tournament.
They will also play a crossover match against the Kiwi Ferns and the President of Cook Islands Rugby League, Charles Carlson, said they will have to do it the hard way.