From that Bloomberg link there's another article that gives a little background.
https://www.miamiherald.com/news/business/tourism-cruises/article242380421.html
Cruise companies are allowed to disembark and repatriate people still trapped on ships around the U.S. by private transportation as long as their executives sign an agreement with the U.S. Centers for Disease Control and Prevention that holds the companies accountable for the process. They are refusing to do so.
In conversations with the CDC, cruise company officials have complained that arranging private transportation for disembarking crew is “too expensive,” according to a spokesperson for the agency.
J
ulia Whitcomb, 24, from Illinois, is one of three American crew members, among 954 total, stuck on the Celebrity Infinity cruise ship, owned by Royal Caribbean Cruises Ltd. She worked as a singer on the ship. She has spent more than a month confined to a tiny cabin with her boyfriend, a fellow crew member, while the ship floats in and out of U.S. ports.
On Wednesday, as the ship was docked at PortMiami, she was told to pack her bags, say goodbye to her Argentine boyfriend, and check out at the payroll office — she was finally going home. But a few hours later, she got a call from Human Resources telling her that the company’s legal department will not agree to the CDC’s terms, preventing her from getting off, she told the Miami Herald.