Which version of aem? How did you promoted & what is status of launch?
Technically if promote was successfully, launch pages will move the content back into production and url will be converted. From your description looks like you have missed some part OR permission issue in workflow package and promote is not succesful. All the issue reported so far are addressed & in fact we internally use it. I won;t rule out the fact there may be niche case it might have broken, i would encourage to engage with official support channel to get it fixed by attaching all the logs.