Maybe this helps us to determine what it is:
Clearly not Indogene writing, my guess would be that it is Castithan or an unknown writing (Gulanee, Sensoth, Volge). I doubt it is similar to the von Bach item. This clearly seems different, but I could be wrong. Remember this is a key and it is not suggested being a "component" of the machine or whatever it is they are after.
Honestly? What it had me thinking until now:
St. Louis was terraformed into a underground city, with a folding over. Something that isn't common for the Voltan races except ONE. Right the people that tried to wipe out the city.
The terraspire with that programming might still be there, and be unique as the Volge were NEVER supposed to be on the ark. Whoever is after that be it the terraspire or not, is trying to do such without drawing attention of the E-Rep and V.C.
Which again points to a DEEP collaboration with Volge.
Again not 100% sure if the St. Louis overlap wasn't just an accident I think there are many areas overlapped due to the failed chaotic terraforming that occurred, in this one case it left parts of St. Louis intact. The reason I say this is because of what we learn and see in San Francisco in the game. It is told that the process literally turns rock or matter into a liquid and reshapes it. There are a lot of rocks that look like waves or the splashes that rise up when you throw something into a pool of water, San Fran is not the only place you come across such rocks, but the targeted San Fran terraform shows this particular process the most. Is it because it is unfinished terrform or is it because of the targetted terraform. The latter could point into a direction that suits/ fits your theory.
I'm thinking Echelon may have a hand in this. They sought to be the third superpower on Earth and if the Kaziri is as powerful as we assume it would be something they are after.
Not sure if this was mention or not, but I found this one amusing:
Rafe McCawley's father was 'Chow Down' Brown McCawley who made dog food
Which would replace our Purina here in STL. Might be a "king of beers" floating around the city too.
I was kinda annoying the mention of Toasted Raviolis and Gooey Butter cake... they do not go well together and finding a restaurant that sells the cake here... good luck. All they need to do now is slide in was thin pizza...