As title says, the DoT from the Pestilence doesn´t harm enemys which have being revived. The way they are revived doesn`t matter. Even through medics or the re-animated event. Sometimes the debuff even refuses to jump on them. And when it does, it does no damage to them. I mentioned this before the re-animated event. But now with the event it becomes more then obviously.
And as an additional bug, sometimes the debuff stops doing damage even when half of the stacks are left.