I don't know for sure what the CCL deadline is but I think you are past it. BUT fear not. You are better off getting your own insurance anyway. Go to insuremytrip.com and find a policy there. most only require you to purchase within 14 days of making your full payment. But that varies from policy to policy. You can normally get more/better coverage for much less from a real travel insurance company.
Carnival Cruise Lines:
Fantasy 90, Celebration 95, Victory 05, Conquest 05, Spirit 6/06, Freedom 6/08, Holiday 7/08, Victory 6/09, Valor 9/09, Dream 6/10, Splendor 8/10,Conquest 8/11,Magic 11/11,Triumph 4/12,Spirit 7/12,Freedom 11/12, Triumph 2/13 - The fire cruise, Magic 1/14
NCL Dream October 2006, RCCL Mariner OTS June 2007, Celebrity Silhouette 2013