The separate copyright notice is because an individual wrote the translation, and this individual holds the copyright, and they claim that the publisher has licensed it to TPF.

  Copyright Credit: Roy Liuzza, "Caedmon’s Hymn" from Old English Poetry: An Anthology.  Copyright © 2014 by Roy Liuzza.  Reprinted by permission of Broadview Press.

There is no copyright notice on Ben Libman's original articles. Libman wrote them for TPF, apparently, and their blanket copyright notice makes the individual ones unnecessary.

If the text is public domain and TPF knows it, where is the declaration of Public Domain? Where is the list of exemptions from "Everything Else We Are Hosting"?

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