I don't even know if there is a way to plug a breach if it did happen. Maybe they could do something to slow it down if it isn't a full-on tear, but if they are trapped in an icefield at that point, I would say it's game over before they could get out in open water to be "rescued".
...and when they were sawing up wood blocks and beams? What was that going to accomplish? If something has enough force to push through a steel-plating hull, I doubt you could build any kind of ad-hoc wooden brace that could structurally augment the steel plating any better than it is on its own.
Margot Robbie is THE most exquisite human creature on the face of the planet, in this moment in time.