I think he left out that ^ ^ point of the evolution, when telling the story to certain agencies and media. But yes, to others, he did include that. But yes, if the G-men who initiated the scans and digs had known of that, then that should have set off immediate alarm bells.
HOWEVER, let's be honest : There are a lot of VERY INTELLIGENT people who are swoon by the notion of psychics and stuff. VERY INTELLIGENT people can be swoon by dowsing.
For example : There has been Medium/clairvoyants who have offered their services to Law enforcement, to solve missing persons, and abducted children cases. And the agencies have sometimes actually gone out and spent lots of department $$ resources chasing-those-leads . Which, of course, always hit deads

. So you could ask the same question about those agencies : Why didn't they just say "no thank you" from the very beginning ?