Look into who they were the debtor to. Turns out that a lot of German banks would have needed to scrap debt from their books.
But in the end, it was clear that unlike in Iceland, bankruptcies were not considerable, and so a bailout was going to happen. The only question was how the bailout would be structured.
Yanis Varoufakis made his name back then by going against the grain and proposing a hairsplit, but instead an approach was chosen where Greece never really defaulted, but its population was harshly punished for it.