A thief asking to return his stolen money is like asking for "fucking respect".
If you deserve it, you will get it.
That's the thing, you can believe as much as you want that he's incompetent and be angry all you want about GLBSE's closure, in the end, he hasn't stolen those funds. He's trying to distribute them and accidentally rerun the script for the 90% payment. Those funds are needed to pay those who haven't been paid yet. Keeping the funds to do yourself your own justice for GLBSE closing down and making you wait? It's the funds of other depositors you'd be keeping. It's not harming Nefario at all, I don't think his reputation could sink lower around here. Only thing keeping the funds can achieve is depriving other depositors from getting their balance paid out.
You can point to other people and say they are the reason why you have no responsibility for your failures. But that is not how I tick. I have hundreds of customers myself and if I make a mistake I always fix it. Even if it costs me money. Customers are never responsible for my mistakes. And I expect the same from everybody else. It is about taking responsibility. Morality will come second. I am sure most people are still honest here and if they feel you deserve it, they will return what is not rightfully theirs. But only after the people responsible for this mess have cleaned it up as good as they can.