Ana is entirely and utterly confused, and makes no effort to conceal her utter consternation at the dark and terrible turn this conversation seems to have taken. She looks back and forth between the various parties present, begins to back away, and fumblingly says, "I'm sorry, sir, I don't understand."
And she makes a point to state it, definitively, rather than allow her tone to rise at the end. Because apparently being uncertain was a horrible crime. Especially being uncertain of whoever this was in front of her she'd royally pissed off. But given the extent of his rage, and her own utter consternation, she leaves, swiftly, after a brief hesitation. She'd figured out what the hell just happened later, unless someone felt the need to stop her on her way out.