Elop would not be anyones *choice* of trojan horse
He's hardly the a high achieving MS loyalist MS would have chosen to send. He was what they were faced with dealing with after the fact.
Make no mistake, MS would have paid a lot to buy a successful Nokia WP business and it's easy to believe they'd hope for Elop to facilitate that. They clearly aren't so keen on the train wreck he actually created (with plenty of help from MS's WP mismanagement), suggesting any 'conspiracy' didn't work as expected and you have to wonder just what leverage Elop had to get re-employed at MS now.
Elop does appear to have outwitted Microsoft though, despite all the other failures.