do these:
get info from barg; he goes away forever
get letter from dirth whether theft or from his cold dead hand
get ledger from isaea's crib (roenall estate, govt district)
i dont think the order you present the evidence matters, but i always start with "he abducted nalia" and end with "he's a slaver". always works for me.
and once ive rescued her, i tell nalia to take a hike. ive got her keep, i dont need her

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