The cloak Madman postulated is like a bubble that surrounds an actual space/time given. Since space and time are inseparable the bubble surrounds them and keeps the information within whatever FTL one travels along. The cloak/bubble extends and preserves its the cosmic microwave background radiation (CMBR) of its birth. Whatever depth one travels into actual ...
This is impossible
First, let me recommend the book Exultant, by Stephen Baxter. It digs right into these problems in a hard-science way. (It's also pretty good.) Most of what I'm about to say is based on that. If this is keeping you up at night, you'll probably enjoy the book.
You're going to run into at least two problems:
FTL is necessarily time-travel
Stash a bit of your DNA is a very secure place.
Say, sealed in a glass vial, along with the usual "time capsule" sort of stuff.
Of course, include some good documentation, photos etc. Be sure to include other organics (seeds, plants, bit of wood, etc).
include a couple of dictionaries, and some nice language lessons on suitable long-storage ...
If this is a time traveler to earth's medieval past there is a problem. Modern finance is not relevant to banking at that time.
The problem was that the Catholic Church forbid charging interest. This killed banking as we know it today.
What was done which was allowed and was done in part to get around this were Bills of Exchange. With these, one could pay ...