So essentially what this one article had to say about Dunkleosteus is that we have lots of really dramatic fish heads, but other'n that we really don't know much about the postcrania, lifestyle, locomotion or how the heads looked on an actual fish.
Related; "Fish Heads," Barnes & Barnes. https://youtu.be/JKDtUzRIG6I
it's my personal contention that the chorus is supposed to be cats.