When all is said and done, it would appear that the bankruptcy will proceed but with the pensions kept off-limits, much as a student loan not being dischargable. Naturally, the pensions are at the root of the bankruptcy so it will be a circle jerk of the first order of magnitude.
I think the pensions would have priority under Federal laws anyway. The judge may have some leeway to reduce the liability, but I would expect the pensions to take the softest hit of anyone.