Other mistake: On the first morning at Manderlay, as the girl is leaving the dining room, she slips and nearly falls but Frith is there to catch her, but Frith was way into the dining room; there is no way he could have been close enough to catch her.
Other mistake: When Maxim and the girl are in the beach cottage after a ship has run aground, Maxim sits in a black chair right next to a lamp that is covered in cobwebs - the place has been empty for more than a year; no-one has cleaned it or been in it, except for Ben, the weird one - but when Maxim sat in the chair, there was no dust rising up and there's not a cobweb to be seen.
Chosen answer: Maxim was previously married (unhappily) to Rebecca, who died tragically and under rather mysterious (and suspicious) circumstances, sparking rumors. Maxim thinks his new wife is referring to that, but she knows nothing about it and was only making an innocent remark, unaware of the rumors. The "rude, hateful" part probably refers to the "dull and gauche and inexperienced" comment - she probably thinks that is what caused his reaction, rather than the "gossip" comment, given she doesn't know the rumors. She is very young and naive and feels inadequate as the wife of a wealthy man. Maxim is older, intimidating her somewhat, and she was confused by his angry outburst.
raywest ★