Also by her saying “he” rather than “it” implies she might have already committed to the thought that Warwick was Vander and only trusted in not fighting when she’d been injured and was further persuaded by Jinx. Also she may have noticed Warwick resist harming Jinx so her protective impulse was lessened and that allowed her to see what remained of Vander and believe in it like she believed in the remnants of Powder in Jinx and the remnants of little man in Ekko.