It seems more natural to have Hermione take an Unbreakable Vow to seek vengeance on Narcissa’s killer (ideally with qualifying clauses). This, in principle, would seem attractive to Lucius even or especially if he can’t reconsider his theory about Dumbledore (or any of his other beliefs). And I vaguely feel Lucius would worry less about Hermione tricking him than if Harry/Voldemort took the Vow. In any case, this approach to vengeance seems directly related to the trade Lucius publicly declared he would make in chapter 80.
This suggestion might work better coming from Draco’s snake-Patronus. They might even get away with adding some lawyer’s conditions then. Sadly, it sounds like Harry couldn’t signal Draco unobtrusively unless he slips away somehow (or, I guess, casts Expecto Patronum into his Invisibility Cloak while muffling the sound). But the time-turner could work here. I was going to say that even a brief disappearance might make L. Malfoy suspicious. But if LM sees him as Voldemort, that would make faking a Patronus intuitively unlikely.
It seems more natural to have Hermione take an Unbreakable Vow to seek vengeance on Narcissa’s killer (ideally with qualifying clauses). This, in principle, would seem attractive to Lucius even or especially if he can’t reconsider his theory about Dumbledore (or any of his other beliefs). And I vaguely feel Lucius would worry less about Hermione tricking him than if Harry/Voldemort took the Vow. In any case, this approach to vengeance seems directly related to the trade Lucius publicly declared he would make in chapter 80.
This suggestion might work better coming from Draco’s snake-Patronus. They might even get away with adding some lawyer’s conditions then. Sadly, it sounds like Harry couldn’t signal Draco unobtrusively unless he slips away somehow (or, I guess, casts Expecto Patronum into his Invisibility Cloak while muffling the sound). But the time-turner could work here. I was going to say that even a brief disappearance might make L. Malfoy suspicious. But if LM sees him as Voldemort, that would make faking a Patronus intuitively unlikely.