The fact that it was used to buy savings bonds, probably mailed to a mail drop indicates sophistication. Bet this is a bigger scam than just one victim.
The old bonds that we once bought at the bank, no longer exist. Most are electronic entries now. A number of years ago I converted a bunch of paper bonds to electronic entries. As they reach final maturity we move the proceeds to our bank account.
It is not a user friendly process, but I’m sure they have an electronic paper trail.