To aspiring authors, don't follow this example.
If you want your villains to get redeemed, than don't make them irredeemable psychos that see other sentient people as cattle from the start.
"They only eat other races because they couldn't raise livestock and didn't know animals taste better" is a morronic excuse.
You can't have a terrifying villain, with a mentality unfathomable to human, like the xenomorph in Alien, coldly killing left and right, and turn it into a lovable scamp at the end because "it tasted caulyflowers for the first time and liked it better than meat" without losing all credibility. That's what's done in parodies, with a group laugh at the end.