Makes me think of "The Lord of the Rings" (One ring to rule them all, one ring to find them.....) and Susan Cooper's prophetic verses in the "The Dark is Rising" series.
It's difficult to recommend any ideas without knowing what role this poem has for your novel. I am going to do my best based on raw guesswork, so apologies if I miss the point totally! I'll be deliberately harsh since charitable comments won't assist you. I proceed line-by-line:
If you're worried about "the cheesiness factor", I'd recommend finding alternatives to hath. I love archaic language, but it can end up sounding a bit silly in the wrong context. Possibilities:
Five Fates for the human world,
Five Fates of the human world,
Five Fates rule the human world,
Five Fates hold the human world,
Five fates fetter the human world,
Five fates bind the human world,
Personally I like "fetter" best, since I'm a sucker for alliteration 
In the next line, is "mould" supposed to be a noun or a verb? If it's meant to be a noun (as in, the mould that grows on food), then I don't know what the sentence means. That said, there might be a special meaning for your story (c.f. the Susan Cooper riddles). Otherwise....
My guess is that it's a verb, which means you are committing the very sin you call trite: forcing a rhyme! Actually, there's one thing worse than this: forcing a half-rhyme, which is what you've done here. The reason I say forcing is that the natural word order would be, "Five pillars mould the corporeal" (subject - verb - object). Actually, although "the corporeal" could be used as an abstract noun (as you have), "corporeal" is really an adjective. It feels to me like this line would be better rewritten as "Five pillars mould [the] corporeal X", where X is some noun. Or better yet, change "mould" as well - it seems an odd action for a pillar to do. Afraid I can't think of anything good right now, though something might pop into my head at random later on.
You can substitute for "hath" again, but the line "One entity the Fates befoul" is okay despite being a half-rhyme, because it's not forced like the previous one.
By the way, it wouldn't take much tweaking to turn this poem into perfect septameter, with two breaks ("Life kills all" and "Reason conquers all"). Just a thought, depending on how rhythmical you want it.
Maybe more later, but for now I should say that it's pretty good already. My ideas are just *possible* tweaks.
wait till i start nit pickin' yer irish ass....
