I've been having the same problem.
Brenden, these instructions are just the basic steps on redeeming iTunes Digital Copies. We've probably all done it before. You aren't really addressing the error message we're receiving.
I get this "code redemption is temporarily unavailable" when I go through the "Redeem" link under the Quick Links section of the iTunes home page.
However, if I go through the links given with the Blu-ray/DVD insert, and am directed to iTunes that way, I go through all the steps fine & submit my code, but then a window pops up asking me if I want to download the movie now or later. I always selection "Download" but nothing happens. (It also says that if I wanted to download the movie later, I can do so "from the movies section of [my] iTunes library," but I don't get that. It doesn't appear anywhere on my computer, in my cloud library, etc, etc.)
This has been happening for the past few days-- using three different movie codes.... from three different content providers/movie studios. (So it's not like one company is having issues.) I've also tried downloading from another computer associated with my account but I'm having the same issues.
Last week I actually downloaded a few different titles with no problems. I'm not doing anything different. Yet the three I'm trying to download this week are giving me these issues.
I contacted Apple about this & their solution was "check to make sure you have an Internet connection," which I most certainly did. 😠