My sister's Outback had the same flaw with the main battery cables smashed between the steel frame and the 2x4 wall framing. Theirs had a circuit breaker at the battery that was repeatedly tripping that we noticed upon arriving at camp.
We disconnected the battery and starting checking things out, eventually discovering the issue. We were able to pull a wheel and pry the wall 2x4 up a bit. We then could pull some slack in the cables out past the frame and wrapped the bare spots up with electrical tape. When done, we pushed the wires back through, clear of the 2x4 and frame. It wasn't easy since there there multiple wires, wrapped around each other and the space we had after prying could only fit one wire.
It sure seems like a breaker near the battery should be a standard item when the consequences include fire and/or exploding batteries.