Why would you have a real
  linkedin account if worked
  at such a sensitive job.

Perhaps he made it to apply for one of the 194 jobs the CIA currently advertises on LinkedIn [1] for jobs like "Cyber Threat Analyst", "Polygraph Examiner", and "Targeting Officer" or to connect with the 1,110 other CIA employees LinkedIn lists.

[1] https://www.linkedin.com/jobs/search?locationId=OTHERS%2Ewor...

You don't have to work a "sensitive job" to be a target. If you are a system admin / in security, leadership role, being on linkedin exposes you. I work in the payment industry and every so often I get the weirdest invites. I simply refuse to accept anyone I don't personally know and I have my profile locked down.

I once had a Field Security Officer who identified themselves as such on their Linkedin profile. Boggles the mind why they did it. Another past FSO always lied to people and told them she was a secretary.