Of course they won't come back and admit they were wrong.
Buckingham Palace made a statement twice, once in April and again last week, to point out that even though the location of the birth and the preparations would be kept private, they would still be announcing when she was in labour as normal and when the baby is delivered. People just saw the "keeping details private" part and filled in the blanks with bullshit.
Ten to one that they'll find something else to bitch about as soon as the baby is born - the name, the wait for a photo, that it isn't ginger enough, that she's holding it wrong, that Harry looks unhappy, blah blah blah blah blah.