Kaeys was obviously lying to look more naive and ignorant regarding his past to Dainsleif, even Dainsleif doesn’t 100% buy it, it contradicts with his ingame story and how he he dealt with the Abyss Order before.
I am pretty sure what remained of Khaenri'ah converted to the Abyss Order
Once again I myself am yet to play the quest. But since I don't care for the spoilers, I've seen the clips and am aware of the contents of the quest, though mostly regarding Kaeya. And I am going to read all the wikis regarding the Albrich Clan. Laying this info out just so I can say "But maybe I'm just missing something"
(NB! This kinda ended up longer than I wanted and sort of wheeled off to other directions and became a full-blown theory post, but but please stay with me, I think I might have cracked the code)
Anyway, I have been thinking about something similar!!!
The quest played out in a way that it implies Kaeya to be in the dark about his linage and the history of his descent. The way he handled the convo, how he was surprised, and how he let out some info and yet didn't know about some other things. It seems almost as if all Kaeya had been told was that he was a khaenri'ahn and the rest of info he has learned and explored himself.
That seems awfully weird and wrong for someone who's supposed to be "The Last Hope of Khaenri'ah". Like, you're telling me your "last hope" is a child who doesn't know about his lineage and barely knows suff about Khaenri'ah. Yet knows (implied in-game) hillichurlian and how to identify a pure-blooded Khaenri'ahn (there's probably more). Idk, seems like sending a spy on a mission without telling them the info/giving them the evidence regarding the mission.
The biggest red flag in his situation is I think – If Kaeya knows this little about Khaenri'ah and overall has little connection to the place, THEN WHY WOULD HE CARE SO MUCH.
Why would he be so torn between Monstadt and Khaenri'ah?
Why would he be so scared of a war between the two sides?
Why would he care about a nation that, A doesn't exist anymore, and B a nation he simply has some blood ties to.
If he wasn't aware of something big and deep, why does he have such a hard time letting go off his Khaenri'ahn past?
To explain potentially why, I've come up with some possible explanations:
As you've said. Kaeya bluffed it all. As usual, he played with the truth. He's actually aware of the baggage clinging to his surname. He was acting unaware, to push aside and cover up the possibly huge role he's been given. "I'm an Albrich...Oh, I don't know anything about my lineage and their plans, how could I possibly be of any threat :)"
And while this is highly possible and I think to a certain extent Kaeya was holding back some info definitely and acting unaware. I've stumbled upon some info that has guided me to form a wider and more extensive theory.
Kaeya truly or at least partially wasn't aware of the full extent of the info regarding his lineage. Because Kaeya's father was the first to bend the truth and cherry-picked what he told his son. So Kaeya's reaction was sort of genuine but he also left out all the stuff he does know. Basically the truth from his side. The truth of who his lineal and direct ancestor is!
Back in the hidden strife event, we learn that Kaeya's dad told Kaeya that the Albrich Clan took up as the regents for King Irmin when he couldn't keep ruling.
Reading the Albrich Clans wiki, I've discovered that in Sumeru, while exploring the abandoned Golems, we as the players learn of the Schwanenrotters, who were led by Knight Marshal Anfortas, WHO ALSO declared himself the Marshal REGENT Anfortas after King Irmin became "indisposed."
Anfortas led his army in the Cataclysm and fought heavily against the dark beasts. Yet it's said that Anfortas fate remains unknown after the bigger events.
I think it's safe to assume Kaeya's dad is referencing the same person, which connects Anfortas to the Albrich lineage and basically makes him the ancestor mentioned in Kaeya's letters.
Anfortas and Clothar both existed at the same time during the Cataclysm, meaning they could not be descendants of each other unless they were in a parental-child relationship. So they were brothers or cousins at best. At this moment I'd add that Clothar, while being of noble class was not close to the king, while Anfortas was (he basically replaced the king). And due to Clothars relationship with a Monstadt commoner, which his family and the Clan weren't too fond of, Clothar was pretty much cast out from the Clan/Family.
Based on all these connections and the fact that Kaeya's dad mentions Anfortas of all the ancestors. I believe that while Clothar is one of the ancestors, but probably a collateral one. It's Anfortas, from whom Kaeya's dad and Kaeya are lineal descendants. And the reason why Kaeya wasn't aware of Clothars exitance or more so his fate, was because the Albrich Clan basically cast him out due to Clothar having a relationship with a commoner Monstadter. So Clothar could potentially be like the weird uncle who your family doesn't speak about.
So Kaeya's dad didn't tell Kaeya about one of their ancestors Clothar being the founder of the Abyss Order, because:
a.) Kaeya's dad genuinely didn't know about Clothar's existence or fate
b.) Kaeya's dad was aware of Clothars existence and fate, but didn't feel it to be of such importance to tell his son. Since their not direct descendants of him. Or he didn't want to spoil the mood with such heavy baggage.
c.) Kaeya's dad was aware of Clothars existence and fate, but due to the Clan having cast Clothar out, their Clan is forbidden to talk about him.
BUT LET'S KEEP GOING FURTHER!! :D
Theoretically, Anfortas could also possibly be Kaeya's Grandfather.
Because going back to way beginning. In Kaeya's story quest, we kind of learn about Kaeya's grandfather. The ever-popular
"Look at my eye patch! I inherited it from my grandfather and this is solid proof that we are related by blood!"
line becomes pretty meaningful in a newer context. This means Kaeya's grandpa had an eyepatch which possibly implies an injured eye.
Well well, Anfortas also had an injured eye, more specifically he injured it during the cataclysm while fighting with Hadura, one of the Schwanenritter. And over all Kaeya's heroic description of his grandpa matches with Anfortas heroic actions as a Regent and a Marshal. Also also, Kaeya says in his story quest "Yesterday I was glancing through the notes my grandfather left...". Could those notes have been from the secret letters Kaeya saved from being burnt, that describe the Albrich lineage, more specifically Anfortas.
Going a bit further because I can't help but notice the parallels between Anfortas and Kaeya. Both have injured their eye in a fight stemming from betrayal. Anfortas was betrayed by one of his comrades. While Kaeya and Diluc betrayed each other's trust during the fight. But the difference was that Kaeya's injured eye is the right one and Anfortas' was the left.
But what would this mean:
Well, there's the whole question of how far related Anfortas and Kaeya would be and if Kaeya is pure blood or a half-blood. And how is Kaeya so human then, seemingly unaffected by the curse. And right now I don't have answers for those.
But regarding Kaeya's position on the chess board. Kaeya, or more so his father's plan is not connected with the Abyss. It's quite possible Anfortas Albrich's lineage is following a 3rd plan which imposes both the Fatui and the Abyss. I think Kaeya's dad's plan is to stop something from happening. The reason for leaving Kaeya in Monstadt and giving him the heavy mission of being "The Last Hope" was because he's hiding his son from something until it's time for their action.
That is pretty much all I have to say right now. This search opened up a new bag of theory worms regarding Anfortas. And I've gotten a pretty new perspective on the whole Albrich Clan matter and Kaeya's descent.
