Pull your heat shield and see if you can see evidence of a leak. The way this is smoking both from the tailpipe and from under the hood makes me suspect a turbo oil seal. If you can see evidence of oil anywhere on your turbo or exhaust, go ahead and swap the other turbo on when you get a chance. If that doesn't fix it, you've either got an internal issue, a breather/PCV issue, or another bad turbo.
