Dude who IS that chick in your sig? I've always wanted to ask, she's getting down
Prophecy? You mean Madam Shirley misunderstood her vision and that Mermaid-Island will be destroyed by Big-Mom and it's going to be blamed on Luffy for declaring war on Big-Mom?
The only thing Shirley saw was Fishman island in flames and Luffy standing there. So there are multiple ways to get there but Oda made clear that FI is not in the clear yet because when Luffy left the island Shirley said something along the lines of that her prophecies always come true.
The only crew who poses as a threat to Mermaid-Island is Big-Mom pirates. The Beast Pirates aren't aware of StrawHats connection to Mermaid-Island and the kingdom is of no interest to Kaidou, assuming Kaidou sort of thinks that Mermaid-Island is still under Big-Mom control. Blackbeard pirates also have their own interest with DFs, weapons and the Revolutionary Army. It would be consider a small fry to care about such issue like StrawHats and Mermaid-Island in Kaidou and Teach's case. Only Linlin would pick on Mermaid-Island as a revenge. I always see characters visit a place only once. I can't imagine to see Luffy goes back to Mermaid-Island.
