If it's an automatic you can find the fob, skrem, ecm set for about $500 on Ebay
The idea is to transplant the identify of the car to another You need the vin of the key/fob to match the vin of the skreem and the vin of the Skreem to match the vin of the ECM make sure that if your is an automatic that the Ebay set is for an automatic. The short of it is that you've entered the Crossfire/Mercedes Skreem hell.