Hall, who is through to the last 24 on American Idol, wrote Oz The Musical, which he billed on its Facebook page as "a contemporary twist on the classic story, with all new music".
He had been putting on small productions of the show since he was 17, using local, nonprofessional actors for the lead roles and casting local children as munchkins and flying monkeys.
Then in August 2008, Dallas businessman Greg Money agreed to finance a production of Oz in Lubbock, Texas, that used a professional cast for the lead roles. That led to a small tour of Texas cities in early 2009 Money says was a "financial disaster".
Plans moved ahead to take the show on a national tour and Money said he tried to line up new backers. Several commitments fell through, however, and the show ended abruptly.
Meanwhile, in several cities, auditions had already been held and children were looking forward to performing on stage in a real musical. Many parents had paid a 50-dollar performance fee that was never returned.
Jennifer Davis, who owns the Art in Motion Academy of Dance, said she was not even informed the show had been cancelled. She found out when she opened the studio for a planned rehearsal and no one from Oz showed up.
Hall was unable to respond in an interview as part of his American Idol contract.