What did The Crown actually get right about Princess Diana and Dodi Al Fayed’s relationship?

Season 6 part one of The Crown has just been released and much of these episodes focus on the relationship between Princess Diana and Dodi Al-Fayed. 

But how much of their relationship which was portrayed in The Crown is an accurate portrayal of real life? Of course, the show tries to stick to the facts and recreate events as they happened, but for many parts of this show, surely some conversations and events must have been imagined for the sake of the plot? Here’s what we know…

Was Dodi engaged to another woman when he began dating Diana?