I've only ever played this mission in non-lethal ending (to get the resultant rune from her after the mission is ended)...

What happens if this mission is handled lethally? Does a lethal ending mean you miss out on that last rune, or are you gifted a rune for another reason? Just wondering because runes largely are given based on the side missions you opt to play and as such the chaos choice does not discriminate (ie low or high chaos will offer the same runes opportunities). Is Lady Boyle's Last Party an exception to this?