The concept is alright but it's plagued by a goofy execution and a lack of polish. The future-cavemen part was the worst of this — placing it second of fifth was the right call, it's the closest the article gets to being comedic, but there's a dissonance with the formatting used (I get that the hazard box is supposed to be taken from an ancient document but using it instead of a caveman class system is disappointing), and the theme looks really bad. I'm pretty sure you took some other theme (New Frontier?) and plucked out bits of code from it, which makes the topbar absolutely unreadable.
The other sections don't do much for me. I get what it is, like a brief visit into each world before moving on to the next, but the picture you get from all of these is far too vague. Sure, RCPA's not the height of well explained lore or anything but it's plagued with details that just go against what's on site tonally ("Americs"? Really? Not Vespucci?) and there's a too much emphasis placed on "it's the Authoritarian timeline" for my personal taste (which most other RCPA articles don't really do better at admittedly, but at the very least those benefit from addressing more interesting themes and having some worldbuilding to chew on).
I think that's the #1 problem here. There's not enough detail on these other-world vignettes to amount to much more than style, which would be fine if the relationship of these two was explored more than just the very beginning and the very end. Without either element being fleshed out much it ends up feeling hollow in spite of how cool the concept is and it makes the climax at the fourth offset explaining how the phenomenon works fall flat.
By the way, the implication that the fourth offset is meant to be written by Howlers had me double take — that really doesn't sound like them, at all, and I don't think it was the right call to write from their perspective when basically all other material about them onsite benefits from their motives being more unknown than overtly monstrous. Like, take a look at the end of 543, the tone is less zalgo-text WE CAN USE THEIR BONES, more "Roman soldiers disgusted at ancient Britain". Maybe I'm misreading how much they're meant to be like howlers. In any case, I think the cosmic/poetic POV is the right call structurally for the fourth offset, though you don't really benefit from adhering to the RPC format. It looks goofy from the mouth of higher beings.
Don't wanna go on forever about these things but there's details like that everywhere that just take away from the multiverse coolness that drives the article. At the end of the day, that's just style — the big problem is that because the multiverse exploration isn't too fleshed out, all the weight falls on A and C's relationship and that aspect is minimally explored. I feel there's a version of this article with about the same wordcount that paints a much clearer picture of these two and why A's always following C around, at an intimate level.
2/5 — the stylistic portions do little for me. It just ends, and it's like, "that's it?"