Aries was well-aware that what she had said back in the dining hall was enough to anger Joaquin. He might snap her neck. But she was certain he wouldn't be so careless to do that.
Joaquin needed to tread on eggshells to win her over because that was already the plan.
To make him forget about Aries, she needed him to reach a point he was hundred percent certain she was Aries and then strike. Causing confusion and showing the difference between Aries and the crown princess would be more effective since the Aries Joaquin knew weren't as cunning and merciless as the crown princess.
She was never the person to exploit someone else's misfortune and death to her advantage. Aries was never that rotten. She could be fearless and terrifying, but her ways were always direct and head-on, not knowing her skull would crash into the spikes her enemy prepared.
The reason Ismael reminded her of her younger self.