Is this authentic if so how is this justified?

Ibn Kathir records: “Ibn Asakir has narrated under the events of Muawiyah’s slave Khadij al Hazi that Muawiyah bought a fair complexioned and beautiful slave-girl and he (Khadij) undressed her and brought her before Muawiyah, he was carrying a stick in his hand and began bowing towards her vagina and said: “I wish this vagina was for me; take her to Yazeed bin Muawyah.” He then said “No! Call Rabi’ bin Umro al Qarshi”. He (Rabi) was a jurist (Faqih). When he came, Muawiyah asked him: “This slave-girl has been brought before me in a naked condition and I have seen her here and there, I want to send her to Yazeed”. He said: “O commander of faithful! Don’t do this. This is inappropriate”. Muawiyah said: “Your suggestion is correct”. The narrator says that Muawiyah then gifted her to the servant of Fatima, daughter of Holy Prophet [s] namely Abdullah bin Mas’adat Fazari who was black and Muawiyah told him: “Make your children white through her”. Al Badayah wal Niahayh (Urdu), Vol 8 page 992 ‘Wives and sons of Muawyah’ published by Nafees Academy Karachi. If this is true that means muawiyah allowed Khadij al hazi to see a woman he does not own in her private areas. How is this justified? Thank you for your response