This is not a real answer to your question but . . .
While we were on the Sun in October one of the staff members (I've forgotten his position but I think it was one of the asst. cruise directors) led a non-denominational service. Granted, he is not a priest but there was a very nice protestant service conducted. The Sun has a nice little chapel which hold about 24 people but this was held in the theatre. You could probably call NCL and see if they know. If they can't make mass they could at least make a visitation to the blessed sacrament while in any port. There is a very nice Roman church in Cozumel and I'm sure in Belize, although there I usually visit St. John's Episcopal Church since my uncle was vicar there many years ago.
One of my favorite things to do in port is to visit the churches. Usually the main church will be Roman but in Belize it is Episcopal because of the British influence. The churches tell you so much about the people if you take the time to really look through them. We put so much emphasis in America on things being just perfect that it is quite touching to see the heartfelt little tokens left at various altars around the churches.
I may be wrong (usually am), but isn't it just the luck of the draw as to which person of the cloth is onboard and then they usually do a non demoninational service that everyone can attend !
When I am cruising I always go the service and it has been a different religous representation at each service but it is structured as such that everyone can join in..As a matter of fact I have enjoyed them and especially like that it takes less then 30 minutes
I asked my TA to check this for me the next time she talked to her NCL contact. She e-mailed me today to say that her contact said there is a priest onboard for Mass on major holidays. I believe that Christmas would qualify as a major holiday!
Of course we can't be sure, but this is a good sign for those who are interested.
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