I came across "Scéal Hiúdaí Sheáinín"by Eoghan Ó Dónaill (https://archive.org/details/scealhiudai ... p?q=cha+dtéim)
and I am a bit confused

The context is that a mother sends his son for a task, he should "go" somewhere, but he refuses:



He will not go, at least he cannot go today, because he will play hurling.
So far, so clear - but:



What does this mean?
mura dtéinn - if I were not to go. Before and after this, "téigh/gabháil" refers to the task, not hurling, so I assume here as well. (mura dtéinn = if I were not to fulfill my mother's task)
agus iad cailleadh - I’ve learned that infinite second conditions following mura are negative, too. (agus iad cailleadh = agus mura gcaillidís). So this means: "and if they were not to lose"

So:
If he would not go (fulfilling his mother's task) and they would not lose ...
means actually:
If he would go (fulfilling his mother's task) and they would lose - then they would (of course) kill him.

Am I right?
It is a bit too complicated for my brain

Why doesn't he say:
Dá dtéinn agus iad cailleadh ...?

Is it possible that mura dtéinn really is referring to the going to the game, which could mean that mura dtéinn agus iad cailleadh could mean 'if I wouldn't go and they wouldn't lose/if I wouldn't go and let them win, then they would kill me'? Why is it not iad a chailleadh is it just a peculiarity of Ulster Irish to omit the particle a?

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I'm an intermediate speaker of the Corca Dhuibhne dialect of Irish and also have knowledge on the old spelling
Soir gaċ síar, fé ḋeireaḋ thíar

But if they could win without his help - why killing him?


Yes, intransitive verbal noun constructions are without "a" in Ulster. "Iad" is the subject.
"iad a chailleadh" would mean (transitively) "to lose them" and "iad" would be the object.

Surely the "rule" you've found somewhere that the second condition is always governed by mura is wrong, or it depends on context???

It's very confusing in English to read all these "would's", because "would" is conditional or past habitual in correct English, and you need the past subjunctive there in the if-clause. If I didn't go and they lost, they would kill me. Of course, Americans mess up the grammar because of the large number of English learners there.

I think it's that he's playing against them, so he has to let them lose. They still want to play the game, hence the mura dtéinn ... mhuirbhfeadh siad mé, but they don't want the dishonour of losing, hence ... agus iad cailleadh (= agus mura gcaillfeadh siad) mhuirbhfeadh siad mé

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I'm an intermediate speaker of the Corca Dhuibhne dialect of Irish and also have knowledge on the old spelling
Soir gaċ síar, fé ḋeireaḋ thíar

I'm not doubting the correctness of your rule, but IF the second clause was in fact positive, then this would be a lot easier to translate (i.e. 'if I wouldn't go and they would lose, they would kill me')

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I'm an intermediate speaker of the Corca Dhuibhne dialect of Irish and also have knowledge on the old spelling
Soir gaċ síar, fé ḋeireaḋ thíar

Hmm, I’ve found exactly the same sentence (in older dialect spelling mur’ dtéighinn) in one of McCloskeys papers*. And he contradicts explicitly my beloved rule using it as an argument for some linguistic stuff.
Perhaps it is really wrong or depending on context.

But the context here was confusing: Many short clauses saying "go to ...", "I won't go", It's better you go", "I'll go tomorrow" all referring to "gabháil síos tigh Ghán" (the task given by his mother), "mura dtéinn" inbetween … But "mura dtéinn" is an unreal condition, and he had already said that he won't go, so that would make no sense.

Anyway, thank you for the answers.




*J. McCloskey, "Ellipsis, polarity, and the cartography of verb-initial orders in Irish"

The iad cailleadh thing strikes me as odd. It should be: agus go gcaillfidís.

Is this the only form used in Cork Irish?

Probably not, but how can you parse iad cailleadh?