Your Australian man is a superb photographer and communicator and I admire his great enthusiasm. Unfortunately, he perpetuates the error that fungi couldn't digest lignin in the Carboniferous. Fungi existed at least 700 million years ago and probably a lot longer than that, and there's plenty of evidence that there were some fungi and some bacteria that were happily digesting lignin possibly even before the Carboniferous. Here's something to google that knocks the stuffing out of the penny-in-the-slot myth: "Delayed fungal evolution did not cause the Paleozoic peak in coal production," a PNAS research article. Take a look. It's a stern read but you should manage it.