[SQLite]

Correct.

"Secure delete" is sufficient to prevent forensic traces from persisting in the database file itself. So you could, for example, send the database file over a TCP/IP link after a secure delete and no deleted data would be transmitted.

"Secure delete" is sufficient to remove traces from the database file itself, but it is not sufficient to remove deleted data from the underlying SSD. That was known from the beginning and should be mentioned in the documentation; if it is not then the documentation needs to be enhanced.