The child's demeanor doesn't change at all. There's no indication that they did or didn't understand. They don't look to his offered hand, instead they have their gaze locked on him still as they keep pointing. They keep their finger pointed insistently. Nothing he said was what they wanted him to do.

But if he looks away from them again for even a moment, they're going to vanish. For as long as he has his eyes on them, though, they can't despawn off screen. They might need to go behind a wall so they're out of his line of sight because this is, after all, a video game.