Packaging for Android fails - Google VR SDK Compiler Errors

I’m trying to build an APK for the Pico Goblin VR headset. Without the Pico plugins the project will compile, but when I add those plugins I get the following Java errors:

\ue4\GameActivity.java:94: error: package com.google.vr.sdk.samples.permission does not exist
UATHelper: Packaging (Android (ASTC)): [javac] Y:\src\com\epicgames\ue4\GameActivity.java:1138: error: cannot find symbol
UATHelper: Packaging (Android (ASTC)): [javac] Y:\src\com\epicgames\ue4\GameActivity.java:2608: error: cannot find symbol

Full console output attached.

I was mistaken, it doesn’t build without the Pico plugins either. I don’t know how I missed that. Errors are the same, with the reference to the google vr sdk etc. I’ve tried building with the Google VR SDK plugin included and without.