I'm currently 20% of my way through his Extradimensionals book. I'm taking notes and I'll do a longer post with more details etc., when I've finished it.
So far, even though he is being quite open and blatant about a lot of aspects of the phenomena, there are other little clues and hints that he drops that show he knows more than he's saying. He mentioned something just as a passing comment about abductions "not just being about soul printing anymore". He's said nothing else about this so far (maybe he goes into detail later on in the book), but how many people outside of those who've studied the C's transmissions have associated the alien abduction phenomenon with 'soul printing'? The C's description of what actually takes place during the regular run of the mill abduction is very complex and involves this soul reproduction idea, related to TDARM if I remember correctly. Most other UFO investigators can't get into this territory due to their nuts-and-bolts and literally physical interpretations of a person being taken by a physical ship.
Regarding the question of why he's being allowed to publish this kind of stuff, I think it ties in with two things, one of which isn't about the fact that he's allowed to publish at all, but is rather, why his work is now being pushed in alternative media who have large audiences? And from what I can gather so far, he seems to going with the idea of gradual to exponential disclosure. His FBI investigative training comes through in every paragraph of his writings so he's obviously not an idiot. He must know that his being allowed to publish work along these lines is itself part of the disclosure project.
My own aim in reading the book is to try to answer these questions that come up about him: what does he know, how does he know it, why can he share it? At this point in time, I think it's possible that he is what he presents himself to be - a former FBI investigator who was kind of sidelined by his instructor and given all the 'out there' stuff, which he investigated in a thorough and unbiased way and now he's retired and is making a living writing about the areas of investigation that he's most interested in.