How do i get my back hatch open? Entire hatch and glass portion wil not open. on 2006 GMC Yukon Denali

Just stopped opening one day. Took it to the dealership and had disagnostic test done- showed nothing was wrong. Fuses were checked with no issues. The dealership said they would replace the entire back door locks for $500, but still couldn't guarantee that it would solve the problem. What else can i do?

Asked by for the 2006 GMC Yukon Denali