Not a substantial post by any means, but I'm thinking that a bit of foreshadowing has been done with dialogue from Mithrax and Lakshmi-2. Mithrax, at the onset of this season with your quest involving the Splicer gauntlet, says that thr City and the Vex network are inextricably bound. He says that one must fall for the other to do the same (paraphrasing). He ends his speech by saying that every Vex we kill sends ripples through thr darkened sky. Regardless he has said that they are bound in a form of hyper parasitism. I'm aware that parasitism may not be the best example, but in this type of relationship the parasite will perish if the host is not strong enough to sustain them. Lakshmi-2 has seen Mithrax standing in the heart of the fallen City amidst gunfire. She believes that Mithrax and his House Light will betray us, but I don't believe this to be so. I believe that she has seen a future in which what Mithrax has said comes to fruition. The city falls and the Eliksni are possibly fighting against FWC who is pushing to prevent the very event they are a part of.