The post fails to mention that the controversy with Marie curie was that right after the death of her husband, she quickly started a romantic relationship with Langevin, one of the students of the husband.
... "right after" being something like 4 years later and not at all scandalous by French standards unless, by chance, there was some organized campaign against her. Ya know?
But anyway, there is a group photo from the meeting that Einstein references in his letter: