Saving Dame Aylin

Just need a sanity check since a lot of the answers on the internet are a bit ambiguous…

If it matters I’m playing honor mode, Shadowheart with high approval, and I’ve made all the “good” decisions like saving the Grove.

I’m about to head to the Shadowfell… if I just let Shadowheart make her own decision (avoid all skill checks) will she choose not to kill Aylin? Any experience / advice on making sure I get the good outcome?