As is the goal of most spinoffs, Fear the Walking Dead has never really come across as a Walking Dead knockoff, despite being set during the same zombie-filled apocalypse, but the companion drama has still struggled at times in carving its own independent path. The back half of Season 2 is thankfully making all the right moves, and that's perhaps best evidenced in Nick's assimilation into Luciana's community, in which a developing storyline threatens to upend everything we've learned about The Walking Dead's mythology! Unless it doesn't.
Every community needs a wise and mysterious older mentor, and Fear the Walking Dead has that in Alejandro, the leader of the religion-centered group that views the undead as a trial from God to test their faith, as opposed to an ever-present threat that needs to be put down. And in Sunday night's episode "Pablo & Jessica," Alejandro confirmed to Nick - and that's confirmed with a whole bunch of air-quotes around it - that he retained his humanity after being bitten by a zombie, and has the scar to show for it. Though that seed had already been planted previously, it was still quite the eyebrow-raising moment for viewers.
Because in the 13 years that Walking Dead creator Robert Kirkman has been telling this universe's core story in the comic books, and in the going-on-seven years the TV show has been on the air, never has there been any sign of cures or immunity where the zombie epidemic is concerned. The closest we've really come is the CDC and Eugene's bullshit story, so this would be as big a narrative game-changer as Alexandria and Negan were for The Walking Dead proper, and the implications could branch out infinitely. I mean, technically Nick could just kill Alejandro at the beginning of next week's episode, thus ending this thread without an explanation, but I don't imagine that would happen.
Honestly, I also can't imagine any of this is genuine fact on Alejandro's part. Living through a zombie bite is the new Holy Grail, making it a highly unlikely scenario for anyone, and your average Fear the Walking Dead viewer doesn't make it through decades of storytelling without understanding that almost all group leaders are not to be trusted in full. Alejandro is a chemist, so it's not as if he's been built up as some nefarious warlord, but just because he's not crazed doesn't mean he's fully on the up and up. You know who else was a chemist, and also a teacher, linking him to Negan's pre-apocalypse life? Heisenberg.
As well, showrunner and co-creator Dave Erickson spoke before the season started about Nick's journey as Season 2 went on, and he mentioned that after he reached a place of spiritual comfort, it wouldn't last very long. The scenario could certainly still allow Alejandro to somehow be a walking miracle, assuming there's more development into how this is possible and what he (and others) aim to get out of Nick from all this. But it's more likely that Nick will soon discover Alejandro's bitemarks have a much different origin from the one he offered up.
That said, I THINK I'd be down with Fear the Walking Dead being allowed to make its mark with a monumental change like this, completely setting it apart from its predecessor. The possibility definitely exists that someone on the planet could be immune to this unexplained plague, and that people elsewhere would have nary a notion about it, which would explain why it never came up in the comics or the other show. And it could possibly give The Walking Dead something to move towards, storywise, should everyone involved be so inclined.
Any way it goes, Alejandro has already become as important as any of the main characters on Fear the Walking Dead. I hope his story remains this interesting, since don't have that many episodes left in Season 2. Keep the faith. Stay alive. Watch out for Chris.