One of our daughters was in the homecoming pageant at her university this week. The announcer was a senior who knew all the contestants and said, "And for the last finalist--Jennifer SoandSo!" They gave the girl her flowers and he looked again and said something like, "Oh, I'm so sorry. It's not Jennifer Soandso, it's Jennifer Smith!"

The girl had to give back her flowers and go offstage.
Last year at cheer regionals, one daughter's squad was announced as one of the 4 who would go to State. For ten minutes, they cried for happiness and jumped up and down and rejoiced, then suddenly someone announced,"Sorry folks, wrong school. It's not RHS that's going, it's LHS." You;d think by that point, they would have let both go--it was awful. The seniors came apart.
How on earth would you play off something like either one of these? Correct it right off? Pretend you didn't mess up? Try to get somebody else to fix it?