The palace knew, it's right there on the statement.
Tatler says it's true, that is in the statement that the editor supports the reporter and the sources.
Whatever makes you feel better, knock yourself out.
Chances are that Tatler has receipts, that is why they are not issuing an apology that what they wrote is false. Nor are they redacting any statements. Because that is all they have to do.
Most likely, there will be no going to court on this. This will be just a threat from W like he did with the Rose story. Telling media to climb down. It will all depend on how much the sources are willing to cross the firm (that will all depend on what generational aristo family they come from).
Unlike in the case of MM, where the media know she has no connections in the UK, the press could dare stand their case because they will either throw Thomas M or the reporter under the bus. If they did make a stand or H&M were the ones who did not want to back down.
Just another self serving statement from W&K.