The Mermaid group are a legitimate company. I work on the freedom of the seas as a photographer and was helped by Ann Powell.
They did charge for an information pack but it was not compulsory.  I think they sell this not to make money but to hire the people who were most serious about the job. They are only a small family run business but the 3 people I spoke to all had previous experience of working on cruise ships and helped me obtain my job. The hours are a bit longer than I thought but great fun in the Bahamas!