A few questions I'm curious what you believe:
Does everyone who ever learned Torah have daas torah? If not, then who is considered daas torah?
Those that do have daas torah, is everything they say daas torah?
Can daas torah ever make a mistake, whether through not getting all the facts, or perhaps if Hashem decides a mageifah should kill many people, He may blind the daas torah from making the correct decision?
What I believe is irrelevant, I can only tell you what I heard from daas torah on this. (Others daas torah may vary)
You're first q I don't think is serious, so I'll skip
The second q, absolutely. Sichas talmidei chachamim tzrichen limud
Third q has 2 parts. 1st part (making mistakes) I can't answer fully, I need to ask my rebbe.
2 nd part, absolutely. We find examples of this in Nach already.
My RY once didn't agree with something from another of the gedolei hador that he had said on many occasions has Ruach Hakodesh.
When asked how can he be mistaken then, he said "Ruach Hakodesh is not a 24/7 faucet". Hashem let him be fed wrong facts, I don't know why.