Ah, very nice perspective on that!
Although I don't get what the beef with the "prophecy" sentence is - "a prophecy that could've been misread".
The sentence is structured to refer to the prophecy (I honestly don't remember the grammatic term for that) - they talk about the prophecy earlier, and Yoda just kinda throws it in as a commentary: this prophecy you're talking about, that could've been misread you know.
Just saying "this prophecy could've been misread" sounds more disjointed and laconic in that context - it wouldn't if we'd just seen Yoda come out of the meditation room, or the library, or having had some sort of meaningful dialogue or revelation, and announce this new, sharp perspective:
"MISREAD the prophecy could have been!" tum-tum-taaaaaaaaaaaaaaaam.
The way the dialog feels, they already kinda know it could've been misread, so a "the x that..." sentence structure makes more sense.
And the "misread" at the place it is, gives it an additional emphasis.