Pretty much. They might've been able to fix it early on, but by the time they realized their mistake, it was too late. It's possible they might make it later. As time goes on, maybe they'll find a house elf, trying to warn them to not go back to school. I heard they're really good at moving cakes, when they're telling you to not go back to school. I also heard they're [i]really[/i] bad at trying to save people's lives, but that's besides the point.