Thank You for the great Tip, Able to get hold apktime apk...little bit tricky, apktime website doesn't show anything....with this able to install Kodi on firestick 4k.But this requires the app to be installed first to your phone. My suggestion to OP is this. Just install single app on your phone named "Apktime" and use Apps2Fire to put in your firestick. This is the baap of all apps (basically source of all apps). Use apktime directly on your firestick to download all apps.
Things like Jio TV etc will not be there but many other apps will be.
Wish Firestick 4k support ex-fat or NTFS formatted external drive.