Forneus debuffs

So I've been battling Forneus for awhile now and I'm aware of it's skill Focused Eye decreasing the chance of your buff to trigger. What I'm confused is that it used that skill to debuff my Waiver and I fired Merlin's NP and I noticed my Quez and Merlin himself miss some of the buffs (e.g. Quez didn't get her mana regen and Merlin didn't get his crit stars per turn). Waiver was the only one with the debuff icon so I'm wondering if it's AoE or a passive skill of the pillar?