I can only hope that this isn't how it happened. If the PI learned of it from either JB or KC while they were in JB's employ it is protected info and they cannot discuss it with investigators. Of course if it was while they were in JB's employ they aren't supposed to be talking about it with anyone, as it is supposed to be confidential/protected info. I am hoping they heard something while they were working for the A's, that info wouldn't be as confidential.
Since they do seem to be talking to media and LP and who knows who all they have talked to, I am thinking that they heard something while they were working for the A's, something that made them think of going out to look in the woods.... perhaps the A's even asked them to go look there. If they did it based on something the A's told them to do or due to something they overheard at the A's, then investigators can not only get that info from them, they can find out who knew what in Nov.