That argument seems to boil down to whether or not a thing can be a member of a category before that category is described and named by humans, or presumably any sentient entity. You seem to ne arguing that it can't, I would say it can.

Considered anything that existed before humans. Let's take dinosaurs. They existed, but before humans came up with the name 'dinosaur' were they dinosaurs? I would say that the category existed even though there were no humans to describe it. Likewise with aesthetic categories, the entity exists and either fits within the category, or it does not, even if the category has not been described by humans. Thus, if you consider fossils to be poetry, they are, indeed, poetry older than words.

If we're nit picking the meme I would instead take issue with the concept of fossils being a memory of bones. We have fossils of plants, boneless creatures and even soft tissue from creatures with bones. Despite that, I think the meme is reasonable enough, and a fair way to look at things.