I meant to respond to this when I got back from vacation, and forgot, so sorry I'm late
My first reaction is that it's possible that the Hebrew
mal’akim is less a name than a title or job description.
beney Elyonor
benev Elohim is the general name for heavenly beings other than God, but there are some that are messengers, which are called
mal'akim specifically. I don't know enough Hebrew to be able to say with any certainty, but that's my first reaction.
In any case, taking a quick look in Strong's it looks like
elohim means mighty ones or judges, not necessarily god or gods (in fact, the KJV translates it one two occasions as goddess, when referring to Ashteroth in 1 Kings). Exodus 21:6 and 22:8-9 all translate it "judges," and "god" really doesn't work in context there. I think the author is making an assumption that
elohim always means "god" or "gods," and that's just not in evidence in Scripture. I think verse 5 of Psalm 82 is reminding these mighty rulers that they are human and that they will, in fact, die like humans do. I really don't think it's strange that the Bible uses the word
elohim to refer to God and to human rulers; there's nothing inherent in the word to justify insisting that it always refer to deity.
The article is interesting, but I really think the problem he's running into is that he assumes
elohim always means god or gods. It's a descriptor used for God, but literally means "mighty one" or "mighty ruler" and can refer to God or men. It does make me think about the standard interpretation of the sons of God as angels in many OT passages, though I'm not sure I like where the author seems to be going with this.