To anyone interested btw, you get it from the "remains silent" NPC. You need to be level 4 with the dark brotherhood and it is still RNG... I tried with a character I had dark brotherhood already levelled and it failed.
Not sure why they thought it would be fun to put RNG with a 20hr cooldown... 😒 I hope this is a bug and not intentional...
The Supplier has always had a random loot table and had a timer between each time so it isn't a bug.
The option one use to get the lead still have other items that can be looted so it's down right RNG if you'll get the lead or not.
I can't say I'm thrilled by it either.
But instead of grinding alts to rank 4 I'll probably just spend the time between each tries (I got 2 chars that can try) I'll just go exploring and questing in peace.
Honestly, it's possibly the WORST game design in terms of the leads yet. a 20hr cooldown between attempts? *** stupid. Whoever thought this was a good idea should be fired.