I searched through the archives and I was never able to find reference to any discussion relating to "bulkhead collapse sound effects" and the fact that they aren't present in the sim.
These were even present in AOTD back in the last century. It was a nice effect to listen for after an attack while diving into the deep.
It has been my feeling that having something along these lines would add to the overall immersion effect....
...every little bit helps ...so they say.
I'm a bit puzzled that someone never at least attempted something along these lines. I hear explosion effects from time to time that are keyed, it seems, to missed torpedoes that detonate at the end of their range. So it seems that bulkhead sounds would certainly be within the realm of possibility.
Just a thought.