Chain hook of trarthus + general's cry

If i'm not wrong, the interaction of this two skills should be: general's cry minions spawn on warcry, they use chain hook skill and they disappear, chain hook of trarthus do the damage when the chain breaks or caster disappear, no? So the dmg should be done instantly when the minions go away, but at the moment the chains keep hooked on the target even tho the minions are no longer there.

Also, they sometimes explode instantly, sometimes not. Sometimes they deal damage, sometimes not. It's very inconsistent.