On home soil Wales would have been hoping to avoid a third straight loss, but the Cooks out-kicked the Dragons to consign them to the wooden spoon in Group D.
In the early exchanges it was the men from the South Pacific who dominated, and their pressure was rewarded as hooker Daniel Fepuleai dived over from close range for the opening score.
Wales managed to reply, as solid defence from Rob Massam saw the ball turned over, and from the following attack it was the North Wales Crusaders man who finished off a flowing move with a try in the corner.
However, in the 29th minute, with Massam involved again, the Cooks would begin to get away.
The winger’s knock on gave the Islanders an attacking platform, and after a couple of promising drives, Keith Lulia scored in the corner.
With the error-strewn first-half coming to a close the Cooks then extended their lead further, as the Welsh defence were unable to stop Isaac John and his dancing footwork.
The Cooks would not rest on their half-time lead of 16-4, and soon after the restart they scored again, this time through second-row Dominique Peyroux.
There was then some joy for the partisan Neath crowd, as Lloyd White burrowed over from dummy-half for the Dragons’ second try.
In the 73rd minute the Cooks completed the job, after Jonathan Ford followed up his own high bomb to receive a pass under the posts for a simple score.
There was still time for Roets to get his second try, as a lung-bursting run from Lloyd set-up the South African-born winger for an easy finish.
Wales: 1. Elliot Kear, 2. Christiaan Roets, 3. Rhodri Lloyd, 4. Rhys Evans, 5. Rob Massam, 6. Danny Jones, 7. Peter Lupton, 8. Ben Flower, 9. Neil Budworth, 10. Jordan James, 11. Ross Divorty, 12. Tyson Frizell, 13. Larne Patrick. Interchanges: 14. Lloyd White, 15. Craig Kopczak, 16. Gil Dudson, 17. Anthony Walker.
Cook Islands: 1. Lulia Lulia, 2. Christopher Taripo, 3. Brad Takairangi, 4. Keith Lulia, 5. Rea Pittman, 6. Jonathon Ford, 7. Isaac John, 8. Dylan Napa, 9. Daniel Fepuleai, 10. John Zebelon Taia, 11. Tupou Sopoaga, 12. Dominique Peyroux, 13. Tinirau Arona. Interchanges: 14. Sam Brunton, 15. Anthony Gelling, 16. Joseph Matapuku, 17. Adam Tangata.
Referee: Richard Silverwood.
Venue: The Gnoll, Neath.