@WylieModro - I was having some similar issues. It looks like Nvidia Codeworks is no longer bundled with UE4 and has fallen a few versions behind. I downloaded Android Studio from Download Android Studio and SDK tools | Android Developers and it detected and updated the Nvidia sdk. I also downloaded the latest ndk from NDK Downloads | Android NDK | Android Developers and pointed my project settings to the path for it. This allowed me to package for ETC. Still can’t package for ASTC but I think that’s because I’m on an old Phenom II processor that doesn’t support a necessary instruction set (AVX).