I noticed that Whitley Strieber believes the FBI memo to be true (and not related to an earlier hoax). In fact, he says he has corroborating evidence/information from a relative.
Whitley has been accused of being a government shill.
Conceivable.
Still . . . from his writing, his blog etc. his personality . . .
I think he tries hard to tell it like he sees it. He’s even quite open to the probability that they are demonic/fallen angel critters—and certainly has felt the evil associated with them.
In terms of that issue, I’d believe him when he says he has a confirming source.