Battle of Khaybar
The Battle of Khaybar (Arabic: غَزْوَة خَيْبَر) was fought in 628 CE between the early Muslims, led by Prophet Muhammad, and Jews living in Khaybar, an oasis located 150 kilometres (93 mi) from Medina in the northwestern Arabian Peninsula.
Shia Muslims believe in and follow the truth only. The narration you referred to is a fabricated one as leading Sunni Shaikhs including Umar ibn al-Khttab never believed that Mut'ah marriage was prohibited anytime during the life of the Prophet (SAWA). That is why Umar has clearly said about Mut'ah: It was allowed during the time of the Messenger of Allah and I am prohibiting it. ( Musnad Aahmad Ibn Hanbal and Sunan al-Bayhaqi and Saheeh Muslim and many other Sunni sources).