Talking about death of the author, I think I came across the furthest possible extent of it

There's an ancient Sumerian...joke? adage? parable? anecdote? That has gotten some attention in the usual places you'd imagine around the internet. Translated to English it says:

A dog walks into a bar and says "I can't see a thing, I'll open this one."

It's built like a joke, but if it was one the humorous element has been lost to time. No one gets it. Not even archaeologists. Hypotheses include:

• It's an aural pun for a language we no longer know how to pronounce. Imagine archaeologists in the year 6000 puzzling over "What's black and white and red all over? A newspaper." That joke already doesn't work in written English because even a native English speaker might not get the pun if they first encountered the joke in print rather than spoken aloud, because the homophones aren't spelled the same.

• It's a vocabulary pun that we no longer understand. "A man walks into a bar. The next man ducks." Is just a non-sequitur unless you understand that the phrase "walks into a bar" means both "entered a drinking establishment" and "collided with a horizontal metal rod." Does one or more of the words in the joke carry an additional meaning that has been lost to time?

• It requires some cultural understanding that we lack. "A man walked into a wiring closet, and was shocked by what he saw." If those future archaeologists reading this joke with no other context don't understand what electricity is, it will be impenetrable to them. There is apparently a hypothesis that Sumerian bars doubled as brothels, so it's a joke about a dog peeking at people fucking.

We talk about "death of the author" in terms of, the author meant something while writing the work, the work means something to the audience when they read it, sometimes these two meanings are different, which of the two meanings is correct/matters? People have read all sorts of meanings into the cockatoo screeching in Citizen Kane; in an interview Orson Welles says the cockatoo was there simply to wake up the audience. If you do find meaning there where none was intended, is that meaning valid?

The person who wrote the above joke has been dead twice as long as Jesus. We don't know their identity and have no metatextual writings from them; no explanation of what this meant to them. We have no way to ask the author what he meant by this, and we don't get the joke. We can read the text and understand its surface level meaning, and that's it.

So...what now?