Lorenzo's backstory: Vacena's navy

Vacena’s Navy is separated into two fleets: the Home Fleet, which protects Vacena’s own waters, and the Foreign Fleet, which protects Vacena’s interests elsewhere. The Home Fleet has been known as the best human navy in the world for a century or more; they haven’t lost a naval war in that whole time. The Foreign Fleet is smaller, more dispersed, and less uniformly successful. Ships sail longer distances in fewer numbers, and encounter a wider variety of situations.
Plenty of officers and sailors serve in both fleets over their careers. There’s no official difference, but unofficially the Home Fleet is the plum appointment, and occasionally officers are transferred to the Foreign Fleet as a kind of lateral punishment—especially for well-connected, politically ambitious people. Who wants to spend their time bopping around the ass end of the world, instead of hobnobbing in the city whenever you can?
I feel like Lorenzo’s mentor is probably a career Foreign Fleet officer, well-respected but not well-connected. Thus they have to reach out to someone outside the military for help. This would also explain how Lorenzo came from Somewhere Hot into Vacena’s service.
Lorenzo came to Malfa looking for Erling, with no more information. He naively entered into thralldom with Erling Sattr—not with Erling House, but with Sattr himself as an individual.
There are a lot of stories similar to Lorenzo’s in Britain’s Age of Sail (aka early empire). There’s also a slight parallel with the story of Squanto from the US.