This wasn't one of the "Fiction" sections detailing events in the world. This was a write up by Icarus about Puck, which makes all of this section shadowtalk. Thus, everything in the entry on Puck is opinion or second hand conjecture, not solid honest fact.
And thus another shadowtalker should call out the poster on this, as for proof, or start running in circles screaming. As you said, the major factor in the shitstorm about the new AIs was the suspicion that Deus might be behind it (but not the knowledge that he was still around). Now somebody apparently has solid proof that Deus is behind something, and nothing happens. Not even a "told you so" from Clockwork. And the "reveal" itself also is nothing but a passing remark.
Hey guys, I just figured out one of the biggest secrets in the 6th world, but that's kinda besides the point. Do you guys think Mercurial's tits are real?Everybody knew Pax was probably still alive
So that's why Puck referred to her as somebody who should be dead and then went to search her, which started the whole "where in the world is Puck" storyline?
You only have to look at some of the discussions taking place between players on this forum for evidence that these two evils returning isn't news. People have been theorizing that Pax is Dr. Shannon or Deus being the annoymous poster, or even the Horizon Consensus
People in the real world also know that Ares has a bug problem since
Augmentation, that does not make it common character knowledge in the shadows
In short, Deus and Ex Pacis may be back, but everybody who can prove that or even present solid circumstantial evidence is going to make a big splash on Jackpoint
The otaku had datajacks, and while it is possible to repair essence loss now I'm not sure Puck would have bothered. Still, it doesn't change anything about the stats of puck as a technomancer. Nor, honestly, does the low AI knowledge skill. (Though given how idiotic Puck has been about AIs in the past you could almost argue he's not exactly an expert on them.)
Puck was one of Deus' top Whites, responsible for the creation of new otaku and later for exterminating rival otaku tribes. That should have given him some significant insights into Deus, the SCIRE, otaku tribes, and other related areas. Which is the reason why he is on Jackpoint, invites are based on valuable information and not good character (think Kane

).
What his stint with Deus should also have given him is four or five points of cyber, back in the day otaku were often heavily cybered and Deus didn't do half-measures. Even if he had wanted to remove all that (and managed to disable the safeties), between the introduction of Revitalization in 2070 and his disappearance in 2071 he simply wouldn't have had enough time to heal the Essence loss.