Your get the problem?
If the feds tried to help out, that means dealing with California, but unlike the rest of the union, California does not allow legislative assembly on the issue of pensions. Unelected union members always have the legal right to participate.
If the federal government played any role, the liability swings right back to California because 49 other groups with the right to assemble will make sure of that. All the others know California is an inside dealer, an asymmetric negotiator, a real nightmare. The compromise has always been to tax the hell out of California to pay for the legal idiots in our legislature.