It looks like the Wizards have filled out their last developmental roster spot. After the signings of Leathers, Marquess, Pardo, and McKenzie recently, there was one spot left on the roster. According to the roster on the Wizards website, it looks like Yomby William has beaten out Kevin Souter and Nelson Pizzaro for the final roster spot.
From checking out Oz City, it looks like Souter was offered a contract, but there were questions with his eligibility. We'll see if there is an official announcement from the team one way or the other.