They were considered important works on various subjects such as history, and that is why the KJB had them between the testaments as being non-Canonical.
The Cardinal is simply broadening the word 'Canonical' to make it mean something it doesn't mean.
The Canon refers to those books that define Christian doctrine and are directly given by God.
The Apocrypha books are not part of the Canon.
In your unlearned opinion. The Deuterocanonicals are not part of the abridged, edited versions of Scripture that showed up centuries after the original. The corrupted KJV, not KJB, was produced over 12 centuries later. However, they were there when the 73 book canon was closed in 405 AD by Pope St. Innocent I.