User blog comment:Hyperborean/"The House of Hades" – official expectations blog/@comment-10487081-20130604012504/@comment-37.105.118.90-20130605120156

You guys are forgetting one thing that Hades/Pluto ignored Hazel as one of the escapees and Hazel herself said that he cannot talk to her unless he obeys the law of the dead and bring Hazel back to the underworld. So Hades/Pluto can't help the 7.