I can only access VR content in Oculus Store (worst search function ever). I downloaded VR titles in Play Store and see the apps on my phone bit can't access them, even when I access the internet.
Not sure but guessing that the VR content you downloaded from google play are only for google cardboard...apps from oculus store really only work with the gear vr. or apk's or whatever downloaded from websites and such that are specifically made for gear vr.