It was March 6th, and New York was still.
Doctor Selvece fished a lighter and a pack of cigarettes out of his backpack and stared at the dead shell of Midtown Manhattan. Corpses lined every street, as did the various things they'd left behind - a wallet here, a beer bottle there. Cars were parked, abandoned, and crashed as far as he could see in either direction; the city was a junkyard and a graveyard joined together in haphazard fashion. Walls were still decorated with graffiti he'd seen a lot in the final few days he was above ground - "THIS IS THE END", "GOODBYE TO EVERYONE", and so on.
As his eyes followed the cigarette smoke traveling upward and vanishing with the wind, he contemplated the closing months of civilization.

DoctorHongSite68: Hello? Is anyone there?
DoctorSevleceSite68: Hong? It's me, Selvece. Verification: "History is a cycle of mistakes."
DoctorHongSite68: Oh man I can't believe you're still alive. I had to abandon Site 68 a few hours ago - there was a containment breach and the MTF we assigned to it almost all shot themselves. How did you get access to this network?
DoctorSelveceSite68: I am monitoring the development of SCP-3519 from my current location. The emergency site FRC was still working, and nobody was using it. Likely because they are dead.
DoctorHongSite68: Yeah, I'm the only one who wasn't infected at 68, as far as I know. I was in an isolated containment unit when the countermeme was deployed, but it didn't make it to anyone else before their infection was irreversible.
DoctorSelveceSite68: That's about as bad as I imagined. I was in New York when things started to get really bad in January and hunkered down in a bunker I had constructed here awhile ago.
DoctorHongSite68: Wait a minute, a bunker? How did the rest of the Foundation not know about it? Were you alone?
DoctorSelveceSite68: Yes to the latter question. I had it built for myself in case the worst happened, and issued amnestics to the construction workers.
DoctorHongSite68: RAISA would've found out about that…just how long ago did you build this thing?
DoctorSelveceSite68: Long enough.
DoctorHongSite68: Well, the important thing is that you're alive, and so am I.
DoctorSelveceSite68: March 5th is still more than two weeks away. Wherever you are, you need to stay away from other people until then. And by other people, I mean everyone but me
DoctorSelveceSite68: From what we understand, the infection has become more aggressive as the date approaches. Countermemes may not be sufficient at this point if you are exposed to an eschatological concept.
DoctorSelveceSite68: Avoid all news outlets still broadcasting/publishing
DoctorHongSite68: Sounds like a good idea. But what about after that?
DoctorSelveceSite68: To be honest, I don't know. There's not that many people left.
DoctorHongSite68: I do.
DoctorSevleceSite68: ?
DoctorHongSite68: There's a place I know the infection didn't get to. A place of safety, free from the troubles of the world.
DoctorSelveceSite68: What on earth are you talking about?
DoctorHongSite68: Sending the file over now.
DoctorHongSite68: Did you get it?
DoctorSelveceSite68: Doctor Hong, I suspect you are currently infected by a Keter-class cognitohazard. I am closing this channel now.
[TERMINATING FRC CHAT #S68Emergency; 15 SECONDS]
DoctorHongSite68: It's not a cognitohazard. It's the truth. And I'm going there once this is all over.
DoctorHongSite68: Good luck with whatever you do, Selvece. I hope I see you in paradise.
[CHANNEL CLOSED]

It took until April for him to read the rest of the file. Part of that was because he'd been occupied with surviving, moving into a nice apartment near Central Park and stocking it with everything his survivalist instincts could think of. But mostly, he was apprehensive about whatever SCP-3891 had done to infect someone who had survived the cognitohazard that everyone else hadn't. What would've been the point of living past the 5th if another SCP finished the job?
But after weeks of trekking through a ghost city now being reclaimed by nature and reading whatever books could take his mind off of his surroundings, his curiosity could be held back no longer.
At first, his worst fears for his friend and fellow researcher were confirmed.

Although the cognitohazardous properties of SCP-3891 preclude detailed investigation, these individuals are presumed deceased given the inability of SCP-3891 to support any significant population for extended periods of time.

He was wrong. There's nothing for us there.
Then he read on.

SCP-3891 has a permanent population of between 250 and 300 individuals,

And on.

being a place of safety, free from the troubles of the world

And on.

Sounds beautiful, doesn't it?

It did.
He didn't decide right away, of course. Duty and obligation still meant something to him, and on the off chance that someone was still editing the files, he might be able to make contact with a survivor if he could find a working connection to the Foundation's servers.
But as spring turned into summer, Selvece formed a curious habit. After spending the morning and early afternoon hunting the deer that were becoming a more and more common sight, he walked to the World Financial Center and stared at a boat that was hastily docked in the harbor. After a week, he walked towards the boat and began clearing out the debris and bodies (mostly skeletons now) inside of it.
By the time July's punishing heat had formed the first rust on the cars, it was ready. All it needed was his supplies. Saying goodbye to his post-apocalypse apartment left him more sentimental than he thought it would, and he made sure to bring his group picture of Site 68's head researchers as he walked out the door for the final time.
On July 10th, New York murmured. It was a rumbling that would have been faintly audible to most, if anyone had been around to hear it. As it was, Doctor Selvece took one last look back at the big rotten apple that Fifthism had emptied as the roar of his boat's engine filled his ears. He wondered if anyone would ever see the skyline again before the decaying power of time eventually brought the buildings down.
He also wondered if SCP-3891 was what he hoped it was. It could be a trap, or simply an empty lifeless atoll. Or it could have been infected by 3519.
Or maybe, just maybe, Hong was waiting for him.
"I don't know," he said aloud. "But it's worth a shot."