I think ships are a bit like the wild west... one of the last “anything goes” jurisdictions. The cruise industry especially goes to great lengths to avoid regulatory oversight at all costs.
Maersk's insurer, or more likely, legal team wouldn't permit something like this because of the liability they'd carry for enabling it. It wouldn't get past that point to a discussion of region-specific employment restrictions, not that they matter here per your comment.
All they (and every other bigco) care about is doing whatever token "due diligence" they need to do. If your papers aren't legit they don't care as long as they don't know.