I honestly think that the author killed ara was probably to show that Arabella can’t escape death in any life because remember she caught the plague in her last life , even though it’s really sad she died..
I agree with your theory- I'm wondering if she succeeds in preventing a death would that be considered "good" or will that strike her against the scales that the gods set?
I feel like its going to get to a point where hes gonna let her kill him idk i hope not T.T