I don't play on PS4, but I do use a controller. I'm familiar with the targeting issues you've described, but I don't think they are the reason why you would lose aggro on any mobs. Assuming you're talking about trash packs, I think it's far more likely that you had DPS inexplicably single-targeting trash pulls and perhaps you may benefit from throwing in one more AoE aggro skill (flash, overpower, w/e) when you first begin the pull. Generally, I haven't had aggro issues in this dungeon unless the healer throws regen on me or something pre-pull, and even then I just have to double back real quick and flash again before moving on to the next pack.