Still don’t believe it happened?
Japanese documentary interviewing 3 ex-members who admitted to practicing ritual sex with Rev Moon.
Tragedy of the 6 Marys written by Chung Hwa Kwak (Though he later retracted, his 3 co-writers did not)
And here are just a few splinter cult groups which originated from UC with ties to ritual sex activity. If you research some of them they have very similar terminology and teachings to the UC.
JMS cult (unconfirmed) – http://www.jmscult.com/home/
Nakayama-Shirabe group – http://www.tparents.org/Library/Unification/Topics/Heresies/Ohta-Nakayama-Shirabe.htm
Tenchi Seikyo group – http://www.hucc.hokudai.ac.jp/~n16260/archive/eng/pdf/formation-of-a-new-religion.pdf (Not originally a UC sect, but tied to UC by shamanistic practices)