My app is a music player that allows users to purchase and stream my demo recordings from dropbox. I provided a signed statement that I own the rights to the content. But Apple rejected my app because "Your app contains content or features that may violate the rights of one or more third parties. Specifically, your app provides potentially unauthorized access to third-party audio or video streaming, catalogs, and discovery services."
Am I correct that Apple needs me to prove that I own the rights to the content? And if so, how can I do that?