
i think you should take the logical way for this for the new ending(in my opinion) and that is to use the word of the dead on lashari
Also to have a ysran go into hiding and you have to follow clues to find him when you track down his hideout you are given a few options
#1
the sneak approach you are given a potion to reverse pickpocket into his inventory ( the potion would be some kind of sedative ) or the 2nd sneak approach you are given a bow that does 0 damage a a handful of of arrows that also do no damage but have the potion from sneak approach #1 on them and you find some place to snipe him with it
then either way take him in and have him interrogated and you and the most powerful warriors and mages guard him
#2 the fight approach you have a boss battle with him and you beat him and when he is about to die and he is on the ground like people in skyrim on super low health are its starts a dialogue and it says cut him with a knife you are given that has the potion(from the sneak approaches) on its blade and it plays out like both the sneak approaches do
also during the interrogation you put on a ancient relic on ysran and this relic would be one you are given a quest to find right before you do that hideout infiltration quest and it would be located in some dungeon or something
the relic would be like something that suppresses magical powers on the person it is put on it on
( i am imagining a handcuff looking thing or a disc you put on their forehead but it is your game/mod so its your choice to do whatever you want ) it would be called something like the arcane suppressor or the blindfold of the sea of eventualities or something ( the lore could be it cuts off the glance to the sea of eventualities on the person it is put on or something )