Other mistake: The designer asking Khrushchev about what type of curtains they should have for the funeral. He first says "ruched" for the sample in his right hand and "not ruched" for the left. He then continues, but instead says "not ruched" for the right hand sample and "ruched" for the left. (00:59:30)
Factual error: Beria was not executed until ten days after the funeral, not on the day.