If this is the case, It's like a plaque on Zorn, How long does the Fearful debuff potential on Zorn last? Same as it does on players? If it's a shorter period, then it doesnt matter how close to Zorn you are as long as you attack Toth during this cooldown.? This may make it easier to just switch to Toth for 1 rotation during this period. The only time I have this problem is when the jump occurs directly after the circle phase, because sometimes the safest path out of them is forward.
Its a 5 second thing. You can't hit zorn with anything when that leap occurs (If you have dots, it actually wipes them off and they need to be reapplied when its safe), its better to just back off or go through a couple of gcds to Toth. I stayed 28 meters away tonight and never got the debuff by swapping on the leap tonight for a few gcds. I think a lot of people are so used to their rotation that if they don't swap off zorn, theyll end up getting the debuff and not realize it until they're dead.
The debuff is applied to everyone within X meters from Toth when Toth lands from jumping to Zorn. It's entirely possible to be 35m+ from Zorn and still get the debuff if you're positioned poorly.
This is what I was talking about with reapplying dots/damage on the leap. You'll get nailed with fearful at that point if ANY Damage hits zorn and you're in range of fearful