So Larian you give us the option to kill Astarion in camp after he wakes you when trying to feed on you. If you have not met Gandrel at this point and meet him later he refuses to believe he's been dealt with, EVEN when I have his corpse in my inventory. Yeah I carried his corpse just to see if there was any change in the dialogue, nope Gandrel acts as if I must be mistaken even if I can stick the irrefutable proof in his face.
Did you all think we wouldn't kill the vampire amongst us?
Or was this just lazy writing?
A simple bit of dialogue with Gandrel would solve this huge plot hole, produce Astarion's body get a small reward kind of thing. Tie's off the plot hole you left for us mean people who kill Astarion when he tries to feed on us.