[Quoth]

Honestly I'm a bit confused as to what he is referring to.

Also IMO Kickstarter and similar only applies to writing a Graphic Novel / Comic where you are writing only and can't do art and have no art partner (see original Asterix books, one wrote the other drew). We aren't all Schultz, Watterson or Hergé (Peanuts, Calvin & Hobbs, TinTin). Or a board game. Neither novels or audiobooks need Kickstarter.

You can pay someone once off to perform a reading and oddly because it's a "hire" they get no royalty or share of profits.

Or if you are good at narration you can record yourself.

Or the "publisher" may have audio rights and have or hire people to narrate. Then the writer gets the usual meagre royalties from a big publisher.

It's not clear what Sanderson is talking about. If Audible or whoever made an audiobook using own staff or hire, then it's a bit like royalties from a movie, except higher, because the book has to be made to a screenplay and then the production compared to recording and editing an audio book is massive costs. You can get a good enough audiobook recorded and have full rights of the audio file(s) as well as the text for maybe $2,000.

So if I gave someone e-retailing copies of files I wholly own I'd expect to get maybe 70%. But if I only own the text then 25% is very generous.
So I don't know what the Audible 45% exclusive and 25% non-exclusive refers to.

IMO narration is a totally different talent and experience needed different to writing.
Narration & audio editing is unrelated to writing-proof-edit cycle. If you have any audio editing experience then editing in Audacity might be easier than making a badly formatted word processor file into an ebook or paper book. However the Narration takes a lot longer than the final hours of the finished product. An average novel might be 10 to 14 hours of narration/listening. It's certainly much less work than writing a first draft of a novel, which might be 1/2 to 1/10th of work (unless you are Antony Trollop or Enid Byton who mostly just wrote & published without edit).
Also narration isn't as creative as acting. It's mostly being good at reading out loud. Audio drama, such as radio soap or radio play isn't the same thing at all as an audio book and both have existed in parallel more than 20 years before radio using recordings and live real time telephone that multiple people could connect to. Hence radio was called Wireless Telegraphy before voice added, or TSF in France (Transmission Sans Fil = literally Transmission without Wire).

So if Audible or anyone else is getting the ready made audio files, then payment per copy should be no different to Apps or eBooks.

If the audio book seller is only getting the text, then while it's not like a screenplay for a movie, you certainly ought not to get as much. If the audio book seller or distributor is charging the entire cost to make the audio book, then that's just like paying someone to reformat your MSS for ebook or paper.

Actually a reasonable 10 hour audio book production might cost less than paying a professional company to fully edit/proof/format a draft novel to files for ebook and paper. So comparison with screenplay and movie costs, or even novel that movie company pays make the screenplay (mor common) and produces the movie is wrong.