I think you'll want something less uhh.. B grade.
The expansion is about the Zinth and new technology from what I can gather, so without further adue (my epic 15 minute session):
AI War: Battlecodex of the Zinth \ Zinth Technobible \ Warship catalog \ Hallowed warhalls of the Zinth \ Zinth armada \ Burnt chapters of the Zinth(pointing towards the zinths vast armory)
AI War: Descendants of *enter some neat named war the Zinth took part in 50,000 years ago to build their ships (they've returned from relative extinction with vast ships, but no society left)
AI War: *name of zinth's most brutal warship*'s Approach. (no one messes with the zinth because they're on mark nine okay?)
AI War: The forgotten Zinthian star (humans discover the planet, and some of the technology, but before long the ai lords crush the resistance and finish excavation)
These are all just shots in the dark, i'm just trying to inspire something more epic here. To be honest, there's alot of room for expansion into AI Wars lore, if done properly, could be as (or more) interesting than homeworld etc.
I gave up creative writing 15 years ago, it probably shows why
I think you really need to build some lore around here. Because we don't really know too much about the zinth, it's really difficult to come up with something good. It also depends why they return.. and why is the AI bothering to chat with them? I always got the feeling the AI didn't care too much about diplomacy.