You got friends that you can play with? The more you can gather up on the original crew the easier it will be, then just sail around with fireworks and hope for the best, I kind of got lucky just running into a large alliance and we had to call in an extra person when one left, we used the discord server lfg. If you can manage to get 2 galleons on the same server by loading them at the same time, even if it's just one person per galleon then you can alliance up and get people from the server who want to do it
This video really shows how unique the sea of thieves community can be, i hope we get to see more stories like this through ur channel! Amazing video!!!