Is anyone still reading this thread?
We’ve gone on 5 cruises, some with a minyan, othertimes not so successful. Food is totally a non-issue. Aside from cholov yisroel milk, which we bring with us, the cruise provides a vast array of pre-packaged, doubled sealed meals, and all the whole, uncut fresh fruits and vegetables you want. just bring along a peeler and knife.
More info if you need.