What this "structure" reminds me of is Preserver-speak. I don't know if this is here or there, and it's just more of my ramblings, but could it be that the Preservers are more literal minded, so the portrayal/translation of their speech is more literal?
What I'm wondering is if "simpler" thinking things might only use a word to speak volumes in that the word in the case of Preserver speech would be a construct of the exact meaning they wish to convey, instead of complext sentances and what not. Might even be a remainder of how they were spoken to on-board the palace before?
If this is so, what we read as... trying to think of a good example... "High-Thing, Do right thing!" or "Growler High-Thing" would have one or two words or sylable combinations or even just basic sounds (they are said to sing, and I keep seeing a reoccuring theme of the meaning of sounds). Reoccuring instances (High-thing, Still-quiet, "Do", wrapstuff, dig-dig etc), might be a simple sound, sylable, etc that is recognisable to the other "palace-speakers".
A further, non-applicable thought is that the "singing" that seems to annoy most of the Wolfriders, Trolls, (and perhaps Winnie, heh heh.) but doesn't convey any apparent meaning except emotion might be the Preserver's origional native tounge, incomprehensible as birds are to us.