***** NOT A TEACHER *****
Dawnngcm, here is a true story.
This week I was watching on American television a "live" session of Prime Minister's Questions (when Mr. Cameron, the prime minister, stands up in the Commons and answers questions from other members).
In referring to another member, he accidentally used a word that didn't seem to make sense. The members roared with laughter. The speaker (the member who keeps order) told the House that they understood what Mr. Cameron meant. The prime minister then smiled and used the correct word that he had originally intended to use.
As you know, the proceeedings of the House are printed. I think that we can assume that only the correct word appeared in the official record.
P.S. You have actually asked a very insightful question. Here in the United States, sometimes when a famous person makes a grammatical mistake, the official record (and newspapers) will change it to correct English so as not to embarrass that person.