being let go......

I started my job as a MDS coordinator approx 7 weeks ago in a nursing home along with another RN that had been there approx 7 months. I had a interview with both the administrator and the current MDS coordinator and explained to both of them that I had no experience in MDS. In the past 7 weeks I have attended 3 days of training on the new 3.0 system and I felt was learning the current 2.0 system with a lot of questions being asked to the other MDS coordinator. Four days ago the administrator of the nursing home called both of us in the office and stated that we had lost the company thousands of dollars for not coding things right.... and also mentioned incorrect dates on entries (which we get a letter from the state once a week and we were not late etc., with any of the documents). Now I have never submitted anything with my name on it.... it has went under the previous MDS coordinators name. The administrator gave us the option of resigning, being fired or being reported to the feds for information being entered wrong!!!! I was so in disbelief I signed the resignation as did the MDS coordinator that hired me........I have alot of questions about this that I have attempted to set up a meeting with the board and have heard nothing back......Why would they hire me under the direction of the current MDS coordinator if they felt she were not doing it right???? Any thoughts from anyone?????? Thank you