I get the same behavior when I do an
import codePush from 'react-native-code-push';

When the app is killed/closed and a notification is received BackgroundService.java (from react-native-gcm-android) is loaded in place of your normal MainActivity.java, but still loads your normal index.android.bundle. I think this is where the compatibility problem is. Maybe if BackgroundService.java could load an alternate bundle file that doesn't contain the conflicting imports? Or the BackgroundService.java could be made more compatible with other native packages?

I would prefer the latter solution since I'm sending data payloads in my gcm's and would like to load enough of my app to at least get access to my redux data stores to save the data. (though I suppose that could also be accomplished with a parred down version of my index.android. js...)