I've noticed that anybody with this problem has been looking for help it took me a week to figure it out and it sucks not having anything there so I figured why not just sideload it ,its A lot easier than trying to adb push it its one simple command
"adb sideload ROM.zip"
Of course "ROM.zip" is switched out for the EXACT file name of the ROM
Of course you still require the android SDK but it is entirely simpler than the alternative
If I helped in any way hit that button