Eh the second you step beyond the gate towards the grove Astarion tells you we'd be better of leaving immediately because the goblins are coming. So without some metagaming involved I would skip the grove entirely.
Also: "killing is fun" = murder hobo = chaotic stupid again.
Following the advice of the Chaotic Evil party member is such a good idea if you don't want to take chaotic stupid choices. /s
The "killing is fun" is an option at the party with Astarion too...
I don't remember all the dialogue options everywhere in the game, but there is plenty to say you did things for your own selfishness even when helping the grove.
