Gonna have to go with Seventh Horcrux's Harrymort in stating that a Weasley majority is a no go for any organization.
Not to mention that nobody else seem to like Ron, considering he's been a dick to Harry all first year, and Shinji doesn't particularly pay attention to bit players.
Although, considering that there is two Ravenclaws in the group, the fact that Sirius black went inside Hogwarts, and did not kill anyone, or do any lasting damage or curse to anyone, would they be able to propose an alternate hypothesis that Sirius Black was in fact, not a Dark Wizard as they had originally assume?