Hope: Escher in the Temple of Space (Theory)
Maybe this is a dumb theory and I'm really grasping at straws here, but hear me out. It's been a couple weeks since I finished playing this quest so there might be some lore stuff I'm not remembering correctly.
Here's what we know as facts:
Young Zandik was an avid researcher of the giant ruin guards in Sumeru during his time at the Akademiya
Dottore disguised himself as Escher during the Tatarasuna incident
We encounter Escher/Maukie during the Temple of Space/Dornman Port world quest, in which he is trying to find a Statue of the Seven in Mondstadt and has lost his memories
Escher/Maukie resided in the Temple of Space until recently
So, this is my theory:
The Escher/Maukie we encounter in the Temple of Space/Dornman Port world quest is a segment of Dottore. As others have pointed out, every time someone's "soul is split" in Genshin, it is into three (for example, Zibai). It doesn't make sense that Dottore would be the only exception to this rule, so I think it's a fair assumption to make that there's one more Dottore left out there somewhere. (Also, not to mention the "Anomalous Tree Marrow ONE") And it makes sense he'd be in the Temple of Space. As someone who researched ancient civilizations (via their ruin guards), he'd be a great person to choose for the preservation the Temple of Space is built on.
Escher was exiled from the Temple of Space before the events of the quest because he "defiled the laws of space". What does that mean? One of the rules of the Temple of Space is that one cannot try to make progress. At his core, Zandik is a person who wanted to make progress by any means necessary - an ideal incongruent with the values of the Temple.
For one to leave the Temple of Space, even by exile, they must lost their memories (as Zeitlind showed). Escher has no memories upon his return to Teyvat. But guess what the Traveler has after the 6.6 world quest? Dottore's memories. Dottore and Pantalone even hint at combining a soul and his memories for a sort of revival. Why is that dialogue there if not setting up a possible future event?
Another weird connection is Escher's search for a Statue of the Seven. In the leaks, there's a piece of dialogue from Nahida (I believe?) that mentions something about a Statue of the Seven, but its location is censored. What could this mean?
Why make it such a central point (the first scene of the world quest) that Escher is back in Teyvat and without his memories if it goes nowhere? We have no resolution at the end of the world quest and Escher (the original, not Zandik) honestly has no relation or importance to the plot. It only makes sense to me that this Escher we see now is related to Dottore. I'm also not opposed to thinking that Escher is the OG Zandik, although I don't know how this could be possible with his death and autopsy (unless it was a lie).
Despite the general consensus on this sub, I believe in the writers at Hoyo. And I sort of like what I've been seeing from the 6.6 leaks, as ironic as that might seem. I think it sets Dottore up as a tragic character, shedding light on Zandik's death and showing his relationship with Pantalone. While I understand the disappointment a lot of people feel, I think we should wait until the quest is actually out (in like 12 hours) to make major judgments about it. I don't think it would have gone over well if they released a playable Dottore right now. For most people, he's still a villain. Then again, that sixth shadow looks an awful lot like him imo.