The licence response lists KIDs a server vault supplied, the client proves them with the decode check, and a bad pair goes to the new session keys/bad route so the server flags its own row. Client vault keys go first over --remote, and the dashboard health warns when no SQLite vault can store flags.
serve.server_accounts lends region-tagged server credentials to remote sessions (round-robin per region, per-key opt-in, per-account cache). Remote sessions no longer fall back to the server's local credentials when the client sends none.