It seems your biggest problem was that you didn't have programmer on "your side" which is absolutely necessary. I outsource parts of projects or whole projects using oDesk and have little to no problems.
Did you really expect the company you hired to care as much about your project as you did? To them you are just money. You said you built your site on top of wordpress, I see this happen most often with low-quality and cookie-cutter development companies. Hell, I used to work for one of those companies and let me tell you quality is not even on the list of things they cared about.
However if you have coder they can review the code written so that they at least have an understanding of it and know how to extend it or which direction to push the outsourced worker in. I'm sorry but if you don't have someone IN your company who can code and you are going to have a bad time.
Did you really expect the company you hired to care as much about your project as you did? To them you are just money. You said you built your site on top of wordpress, I see this happen most often with low-quality and cookie-cutter development companies. Hell, I used to work for one of those companies and let me tell you quality is not even on the list of things they cared about.
However if you have coder they can review the code written so that they at least have an understanding of it and know how to extend it or which direction to push the outsourced worker in. I'm sorry but if you don't have someone IN your company who can code and you are going to have a bad time.