I guess it's less a matter of right and wrong than terms and conditions? Break the oath, the *way* you're meant to use the power and... lose the power?
Oath of the Ancients pretty clearly can't disturb the natural order by releasing 7000 vampire spawn. It's just weird that killing them is fine. Considering the paladin probably sees Astarion as a real *person* at that point. Are you killing 7000 people in your mind?
We know even one evil non combatant can be not fine, so this is really... absurd. Not that one of them breaks your oath, but only one. To me, at least. Fucking up and being granted forgiveness for trying your best doesn't break my suspension of disbelief at least. For all I know, this isn't even punishment. Your Paladin could be having a crisis of faith and waver.
