Something that really catches my attention in this note is simply the fact that it exists - I mean, it's not like this note tells us anything that we didn't already know going into Extinction, so why include it, especially in the Gen 2 chronicles of all places? Maybe the point isn't to tell us something new about Aberration or the ARKs, but to reintroduce Santiago to the story? I mean, Santiago is a major character in Extinction - where the next set of Gen 2 chronicles will be - as well as ARK II, so at least then it would make some sense if they wanted to expand upon his character and story going forward, by, I dunno, putting other notes similar to this one in the other maps?. But still, why include that in the Gen 2 chronicles of all places, unless...
...unless he has some significance in the story of Gen 2? I mean, we see in the ARK II trailer that Santiago likely came from one of those incubation pods that we've only ever seen on the colony ship, and that he's clearly familiar with the GenSim, which we've also only ever seen accessed from the colony ship. Yes, I think that's it - they want to tease Gen 2 and especially ARK II by reintroducing Santiago to the story, both on Aberration and possibly the other maps.