Maybe begs the question of whether hell is a "place", such that all beings in that "place" are hell beings, and hence subject to "hellish pains", etc. Though I'm also certainly NOT implying that "hell" and other rebirth states are simply "mental states", eg. "being in prison is hell", etc. Just asking whether or not the "hell officers" are rightly speaking "hell beings" in the sense of those who suffer the incredible pain of the lowest of the three lower realms. Similarly, although they are "inside a prison", we usually don't consider jailers or prison wardens to be "prisoners", do we?
My recently moved Blog, containing some of my writings on the Buddha Dhamma, as well as a number of translations from classical Buddhist texts and modern authors, liturgy, etc.: .