Pretty sure the cruise lines don't need me to tell them about Bahamian policiesBetter tell that to all the cruise lines planning to lean heavily on their private islands. I suspect if a cruise line says, “we will stop at the private island-only to work out our protocols for Nassau’s safety before returning there in a few months,” they’ll get approval. Everyone wants to be certain the ships can sail safely, and they need to have actual cruises to determine that. The other option is to start allowing cruises to no where again.
Additionally, my understanding is that the initial sailings to "work out protocols" will not have any ports of call. They will use volunteers as passengers, probably company employees and/or family of the crew. Once they are cleared to carry actual paying passengers, then they'll have to deal with Bahamian politics. Nassau wants those shore excursion dollars. We'll see, I guess.