I'm gonna take the middle of the road here.
Yes Hydaelyn is getting desperate, but does it excuse her luring her  most devoted follower into certain doom and using her as a mouthpiece  in a batman gambit? Answer: No. In this I agree with Lucifer, Cilla and Fenral
That said, I'm of the opinion that we need both sides of the story. That  we should be question why did the Ascians wiped Val off the map and  why did out of all the potential echo users there, did Hydealyn choose  to save only Krile? We shouls also ask what would Hydealyn do if we  returned The Crystal (Ball) of Light that currently resides in Matoya's  cave, and what would Elidibus and the Warriors of Darkness do if we  decided to join them. As well as what the entities in question would do  if we refused.
At this point I'm gonna say that both crystals should be suspected of dishonesty and Machiavellian plotting, and not to be taken at face vaule without the proper context. We are ultimately a piece of a cosmic chess game, but the  possibility that we might choose to have a say in how this match goes  might occur.
 
As for the Scions, I feel like this quote is appropriate:
"He who fights monsters should see to it that he himself does not   become a monster. And if you gaze for long into an abyss, the abyss   gazes also into you." — Friedrich Nietzsche,