I had this same issue. The reason the link is not working is because the app must be published before the link will be active. I repeat the app must be published, this does not mean there must be an APK in production. On the top right of your applications developer console page there is a drop down menu that allows you to publish the app. That link will become active immediately and your app will be available in a few hours to your testers on the Play Store.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…