There is a verification period that takes place after the recordings and before judging. This is when directors listen to their students' recordings and verify it is them and approve for them to go on to be judged.
TMEA and MusicFirst developed a great method for students to still have the ability to safely participate in an audition situation. It may not be perfect, but neither is what we normally do.
By the way, most of my college auditions were recorded on tape. I had the ability (if I wanted) to record multiple times. Recorded auditions aren't something new.