He talks about the type of thing said about him on social media in the talk he gave (there's a thread on it). Can't remember the details but he thinks a lot of it came from BP. Aiming to shut him up and not pursue the RF in any way. So it's no surprise that there's some attempts at undermining him going on.
They need pursuing as the reality they present about themselves needs to be held up to as much scrutiny as possible.
Lownie and Norman Baker seem to be the only serious contenders.
As for William and Kate. They are the golden couple, they are the very thing the monarchy hinges on in order to continue.
I've no trouble believing they've had marriage counselling, they seemed to go through a "patch" a few years ago.
The Hanbury thing (and the pegging, remember that?), maybe, who knows, but if Lownie has sources then BP will definitely want to shut him up by discrediting him.
Also, if I wanted to keep open possible good stories with W & C, I'd want to distance myself from Lownie.
So, I guess we'll find out sometime.
I don't warm to the man, sometimes he comes across as this being personal, but then he remortgaged his house for the case to release Mountbatten documents, and he's experienced a vendetta against him by BP so I guess he's just decided to go all out.
I'd hold back a little if I were him, even with sources and evidence, because the public's fickle and it might backfire.