Is the predicate nominative a noun or pronoun?

Either, but if you need to pick one it would be noun.

Explanation:

The predicate nominative (or predicate noun) is the noun or pronoun that comes after a linking verb. It renames the subject of the sentence. The sentence should still make sense if you switch the predicate nominative and the subject.

he or she may have a different tone of feelings.

recent news about two years ago indicates that a polish forestry student by chance unearthed at a depth of about 40cm (16 inches), during digging in a damp polish forest he found a 13-page manuscript into a thermos flask.

greek jew marcel nadjari was a aischwitz slave who witnessed how the nazi's built big death chambers and crematoriums and told how he was forced to escort fellow jews to the gas chambers. he accounts on this manuscript how the nazi's disguised this chambers to look like showers. also, he describes this place as a process of extermination from the chambers to the trains arriving to take the bodies.