Who said anything about "five nines"? All we know from the article:
A couple of hundred claims a week would be a lot in normal times, he says. When the coronavirus hit, millions of claims suddenly were being filed and hitting the front end, which could not handle the massive increase in volume.
I'd say it wouldn't be that critical if was down half the time.
Not sure of these "millions of claims" were submitted within days, weeks, or months. So we have no clue about the volume. Maybe a single server would be fine. But who am I kidding, the cheap Javascript guys will probably build a distributed cloud monster anyways...
I like that many (all?) of the Mausritter one pagers have a d6 table of hooks when using it for a one shot. It gives a little randomization to the start and can result in very different stories.
Luke seems to have campaigns in mind where characters bring context and background.