A mole is someone that is there undercover. Nokia's CEO is there in plain sight and has very strong connections to Microsoft, was brought in by the board to guide Nokia away from their homebrew stuff and onto Windows.
That is what I was thinking, you could ask "is he a colonial governor?" You know, the guy the Colonial power installs as the head of state insuring that the colony will endeavor to make its patron state wealthier at the expense of its own citizens.
The Nokia board of directors probably hired Elop because they wanted to transition to Windows Phone. Elop's job was to the bearer of bad news (to employees).
I was under the impression that they wanted to transition to Windows Phone or Android. Anything to help them become/stay competitive in the mobile space.
How could he possibly be a mole?