but in the examples you give the imprison was 100% and i know this as me aswell as alot of lvl 83+ people in my group had a few new lvl 20 members use it on us and it worked 100% and if we take from what the mod says (His mystery is working as intended. With such passives like Genjutsu Mirror/Root of Warrior, they're immune to the first status effect/Complete Immunity considering his mystery counts as a debuff prior to the action.) then we know the only part that is a buff/debuff is the blind not the buff remover.
also if you trying to say we can not go based on his standard attack the mod also stated that it was a translation error and was meant to be a chance. also most if not all people at the same lvl or 3-5 lvls higher wont have the amount needed to stop the debuffs unless you put onigiri money in power on the game