But really if they had liquidated GM, sold off the assets, would they have only paid 30 cents? Basically they ignored the law, made a deal with the union and the bondholders and that was that. There was no attempt to determine the value of GM at the time and divide that among the bondholders.
Technically bankrupt, but not really. In a bankruptcy the assets are divided amount the bondholders. In this case the assets just continued to be GM. It broke all existing law and precedence. The idea was that if they really shut down GM and divided the assets it would be too big a loss for the US, so the government stepped in and made up a special "bankruptcy".
Anyone thinks they can sue is delusional. They did this to GM bondholders in the US, you are crazy if you think Greece would do better. Actually I had GM bonds, and made money but I bought them cheap. Long term holders were screwed, and as far as I know GM is still in business.