I've thought on the Vasudan language recently, and I think it might be related to their governmental structure (go with me on this).
Vasuda is a desert planet, and that kind of means travel between the various tribes of pre-space flight Vasuda was probably limited at best (who wants to trudge across the desert where the surface water is more than undrinkable?). So the various "tribes" (for lack of a better term) probably didn't have a great deal of contact with each other, which means they developed their own languages (just like us, actually).
However, at some point, one rose to the top and that's where the Emperor can trace his linage. While some of the take over was likely by conquest, some was probably peaceful, meaning wiping out the local culture and language was not possible. "Ambassadors" from the various tribes within the newly formed Vasudan empire would bring their language to the Emperor's court, but it's possible and likely the Emperor only wanted to hear his own language, so they would have to speak it there.
Now fast forward through the next 10,000 years, and the location of the various tribes, their status and such shifts and moves, and then formalizes, and thus the languages become formalized in the same way. If you're in the Emperor's presense, you speak the language of the imperial court, but if you're further out, you speak a different language, and farther out a different one, then other things, probably holidays and such, get into the mix and the language explodes in size and complexity.
So, what is likely is the Vasudan langauge ISN'T one langauge, but multiple languages that got mixed together. How does this relate to the government? Those ambassadors likely spoke to one another quite often, and eventually formed the first Vasudan Parliment, and eventually they pulled a Magna Carta on the Emperor and took over control.
So if you want to learn Vasudan, you would basically have to learn EVERY one of their languages, which is akin to learning every language on Earth. Not easy, by a long shot. Probably the only thing that would help is that there are probably a few more common languages (perhaps even a one for Vasudans who live outside of Vasuda Prime) that one could learn, but to truly learn Vasudan would take a talented person.
It's just a thought and theory, nothing more. Would explain a few things.