It's okay, she's already turned on her heel to go. The downside of this, of course, is that she's... going.

"Help him?"

But okay, she pauses and looks back at him for that, with an expression like he's a stone she found in her shoe.

"What a turnaround for you, Mr. Sinclair."

Tenenbaum puts exactly zero effort into sounding like she believes him. Remember, she knows what you sold for medical experiments last summer!