If your judges have (or are willing to create) Tabroom.com accounts, you could use the Public Judge Signups feature. For each judge category, go to Settings > Judges > [category] > Hires and scroll down to the bottom. You can enable public signups and set a deadline. Then, when your tournament's registration opens, there will be a Judge Signup tab next to the Register tab on the tournament's public site. Once a judge has signed up on this tab, you can review their credentials before activating them for use in the tournament.