I have always been unable to verify the bonides of such folks, and just being in the intelligence services is not in itself verification of the actual role someone had. For instance, Jim Serivan who was in the Clandestine Services division at the CIA tells us nothing about if his role there intersected with anything having to do with UFOs. He unsurprisingly does know alot about how things in the intelligence services work but that also is not verification of anything in his official work that was related to UFOs.
In so many cases we are left with trying to just take what folks say at face value.
Semivan has been very clear—he had no official role having to do with UFOs.
He is relating his personal experiences—nothing more, nothing less.
There are thousands more all over the world in all walks of life just like him.
Imho many of them are telling the truth as best they can.