I'm not sure how an inanimate object can lead someone. Even "guide" would be exceedingly strange, if we're not talking about a topographical feature, an astrological feature, some monumental building or some ideological symbol. I understand what the sentence is trying to say, but in English, might it not be better to translate it as "My throne is a touchstone for my knights." ?
I'm also confused by this. I generally don't mark sentences in High Valyrian as incorrect for being unnatural because they tend to have meanings from the canon that aren't necessarily natural in typical English use, but I'm not sure about this one.