DOD has already contracted for it.
>Why didn't…
Because book of Enoch was written 3000 years after Enoch lived; is concerned about second temple things and hellenistic things when it should be concerned only about first temple era things, but hey they were making a story to try and get people to follow God. Don't worry about the descriptions of people written 3000 years after they lived, next thing you'll be going around saying that Jesus was a bald black woman.