Uh oh. Looks like the "babysitter" set your training back a smidge.
I think you'll either have to live with some "barking" while retraining or modify your environment a bit. But don't give in to any table scraps. He'll learn that you won't be giving in.
I'd definitely start incorporating him into your area of the house, though. He'll want to be with you, and you'll want him to learn to be a part of your life. You can still do that with an x-pen, but I'm assuming that you'll eventually want him to be able to run around the room that you're in.
Good luck - sorry you have to backtrack a little bit.