Lavellan stops short, already turning to go once Rinzler walks past and seems to be ready to continue with his own investigation. He hadn't been expecting any further acknowledgment.

But then he says that, and it's like his mind blanks out, not quite processing the statement. Part of him wants to argue again, insist that there's no way that will ever come to pass--

But, deep down, he knows there is still a possibility. There's still a part of him that wants to go back even now, that misses the stability they'd given him.

So what he says instead, is: "I'll hold you to that."