I uninstalled the sideloaded .apk and attempted the workaround... but it's not working for me. Can anyone confirm this loophole is fixed (and anyone have the address of the updated apk?)
I uninstalled the sideloaded apk yesterday as well and got the workaround to go to the permissions page in the Play Store, but the install button was not there. So I believe they may have patched the loophole. You can find the most recent APK on the XDA forums.