Yes, just take her assistance for granted, no need to consider her explicit wish for them to stop fighting in return. She can feel tried and true contrariness rising in her, but she knows it's mostly just her overall situation making her irritable, so she tries to rein it in. It's good he knows he can rely on her at least.

But he doesn't make it easy to be lenient, when he has the nerve to doubt her, and she shoots him a deeply scolding look. "Of course I am sure." Since when would she be in the habit of claiming something as fact that she doesn't know to be true? Honestly. "The energy signature remaining from our universe is quite distinct, and both he and his TARDIS lack it."