Currently after using the /hidereplay command in a battle room you are stuck with a private replay forever, there is no command to reverse this. As well as there is no way on the replays page to public the private replays by whoever owns/uploaded them if you ever feel like it or decide to. I think it would be a nice quality of life update to have the ability to public the private replays by both a command in the battleroom say like "/publicreplay" or "/showreplay" and an extra button in the replays page for each replay to "public" that specific replay since battle rooms can expire and render the command useless causing the same issue brought up in this post/thread.