What bothers me is that after everything the SH have been through and all the news in the newspaper, the SH Grand Fleet didn't come to aid. So I have a small theory about this.
Wano is not an island easy tracable. Luckily the SHGF had Luffy's vivre cards. They have seen it burn down slowly, so they started moving towards Wano. But they were late...and when they almost arrived the Vivre card burned up. Luffy was dead in their eyes. Days later the newspaper came out that Luffy took over Egghead. A place more easy to find. They were not that far from there.
I think that they are able to back attack the Marine ships ready to attack the SH. That way a distraction is made for the SH to escape. The GF will follow them to Elbaf after.
Wano is not an island easy tracable. Luckily the SHGF had Luffy's vivre cards. They have seen it burn down slowly, so they started moving towards Wano. But they were late...and when they almost arrived the Vivre card burned up. Luffy was dead in their eyes. Days later the newspaper came out that Luffy took over Egghead. A place more easy to find. They were not that far from there.
I think that they are able to back attack the Marine ships ready to attack the SH. That way a distraction is made for the SH to escape. The GF will follow them to Elbaf after.