[They've looked pretty much everywhere, but there's a chance--a slim, slim chance--that they overlooked something, or the currents might wash through a clue for them. URSULA might say that she missed something on her scanners. It's barely a shadow of a chance, but it's still better than nothing.]

She could have been exploring, or looking for supplies. We don't know why anyone else who vanished went out, right? Anything's possible.

[He's already putting on his mask again, ready to head back out.]