this: if something that long bends due to a structural failure like the 1985 movie, in this case, the bottom would be crushed and mangled due to compression, while the top would be cleanly cut because it is being pulled apart.
as you say, "and those two parts of the hull prove what really?"
let me answer that for you: JUST THE OPPOSITE
the break up was interrupted, by what? easy, the only part of the ship that had yet to fail, the double bottom.