I have attempted a translation of another classical poem. This time, it's "The Second Coming", by William Butler Yeats. The version of the poem I used can be found here: https://www.poetryfoundation.org/poems-and-poets/poems/detail/43290

cha'DIch ghoS [1]
[1] I'm basing this on the controversial canon from the SkyBox card where {wa'DIch} was used as an adverbial for "the first time". I wanted to keep the idea of "second" in the translation, because of the religious connotations of the "second coming", so I didn't use {ghoSqa'}. I didn't use something like {ghoSpu'ghach cha'DIch} since I wanted to avoid {-ghach} as much as possible (though I still ended up using it elsewhere). {cha'logh ghoS} suggests both comings, not just the second one. So I'm rolling the dice on the adverbial {-DIch}.

I don't remember the SkyBox card that uses an ordinal as an adverbial. Which one is it?

paq'batlh uses ordinals as adverbials, but the meaning is a step in a sequence:

wa'DIch Hegh moratlh
First, Morath fell
...
ghIq Hegh qanjIt
Then, Kanjit fell

cha'DIch ghoS would therefore mean something like, secondly, he goes, as if this is the second thing he did.

The best translation may be pawpu'ghach cha'DIch second arrival. There's no reason to avoid a perfectly good suffix like -ghach if you're using it correctly. The advice to avoid it applies only when there is a tendency to overuse it. If you absolutely have to use cha'DIch to mean a second something, then you also have to apply it to a noun normally. -ghach gives you that.

I chose paw instead of ghoS because coming (n) means approach, arrival, advent, which is exactly what paw means. ghoS means a bunch of other things you don't want.

Sachbogh ghoDaq tlhe'taHqu' 'oH.
wamwI' QoylaHbe' wammeH bo'Degh.
Sab Dochmey. ngaDlaHbe'taH botlh.
qo'Daq chutmey Hutlhbogh nugh'e' 'uchHa'lu'.
bIQ'a''e' HurghmoHbogh 'Iw 'uchHa'lu' 'ej Dat
chuntaHghach tay SoD bIQ'a'.
pagh Har nIvqu'wI'pu' 'ach
pe'vIl nongqu' QIvqu'wI'pu'.

tugh vay' 'anglu'bej.
tugh cha'DIch ghoSbej.

You can't escape that this means Soon, as a second step, he surely goes. If cha'DIch absolutely must be there, you need tugh qaS pawpu'ghach cha'DIch.

cha'DIch ghoS! mu'meyvetlh vIjatlhpu'DI'
SIbI' mInDu'wIj Suj
mIllogh'a''e' Delbogh qo' qa'.

If Yeats felt it necessary to use a Latin term in an English poem, there's no reason for you to use anything but Latin either.

I don't think you want -'a' for vast; that's more like tInqu'. Replace mIllogh'a''e' Delbogh qo' qa' with mIllogh tInqu' Delbogh Spiritus Mundi. Stick an -'e' on tInqu' if you're not concerned with any kind of meter and you think you need to disambiguate the head noun.

Deb voghDaq QIt 'uSDu'Daj vIHmoH
vIghro''a' porgh loD nach je ghajbogh tu'qom.

I recommend putting a comma between porgh and loD so the reader knows where one noun phrase ends and the other begins. It took me a while to figure it out.

pagh lu'agh mInDu'Daj 'ej vupbe' bIH. jul lurur.
Dechbogh retlhDajDaq jIr Deb bo'Deghmey QeH QIbmey.
pumqa' QIb 'ach
cha'SaD DIS poH QongwI' let
najHa'moHpu' Qombogh ghu QongDaq DaH 'e' vISov. [2]

[2] {Qom} isn't the right word here, but earthquakes at least fit the apocalyptic tone, and there's not much else to use. Maybe one of the airplane movement verbs?

I think the word Dav sway can be used outside of aircraft. At any rate, its explanation by Maltz doesn't say it's specific to aircraft. It's not quite rock, but it's as close as we've got.

I don't understand what stony sleep means in the original, but I'm not sure that QongwI' let hard sleeper fits it. (When let says it means hard (like a stone), that doesn't mean let means stone-like. It's disambiguating from hard (difficult).)

'ej tagha' repDaj lop Ha'DIbaH naQbe'
'ej boghmeH betle'HemDaq yItlI'. [3]

[3] I would appreciate any suggestions on how to better translate "slouch". {yIt} just doesn't seem to cut it.

A literal translation might be yItlI' 'ej yepHa'lI'. Or maybe add SIbI'Ha' eventually to the start of the sentence to suggest that the walking isn't especially motivated or brisk. Maybe also add QIt slowly along with it. Something like 'ej SIbI'Ha' boghmeH betle'HemDaq QIt yItlI'.

majQa'! This is the sort of translation I like: you've done a close reading of the original and remained sensitive to what the poet was trying to convey, rather than just convert the words grammatically. You tried to replicate the feel of the poem in flow and concept without being ungrammatical with a call-out to poetic license as an excuse for things you couldn't make work.

-- 
SuStel
http://trimboli.name