So my previous assumption was correct. The Yellow Dragon Kami was nothing more than an observer, able to affect nothing beyond the vessel within it resided.
This does make me wonder how the dragon deities were able to create the dragon warriors in the first place, but that's beside the point.
What I don't quite understand is how the dragon deities went mad/lost their powers. Was part of their covenant with their respective dragon warriors to not interfere or forcibly bring "Hiryuu" back to the heavens, a condition they broke the moment Yona entered the chalice? Or, while the Yellow Dragon resided in its chosen warrior, able to watch the mortal world go by, the rest of the dragon deities grew as desperate as a kid with ADHD in an empty room, slowly making "amendments" to their covenant that were, in fact, breeches of the contract? I'd rather like some clarification.
But it does look like we're at a stalemate at this point. Yona and company can't leave without the approval of the remaining dragon deities. Base on my understanding of this chapter, the dragon deities have maybe the tiniest sliver of their original powers and, outside of the kingdom losing divine protection, have no ability to impact the mortal world, but they still insist Yona accept their unreasonable, half-mad terms.
Honestly, I know it would break a lot of elements of the story thus far, but I keep wanting Yona to reclaim the former powers of the Crimson Dragon and become a supernatural being if for no other reason than to wipe the floor with the beings that keep standing in her way. XD
Oh well.