Well, what you describe, is the SKREEM not telling the ECM that it's "Ok to start".

So, if you changed the SKREEM and ring and it still won't start - why would the NEW SKREEM also not work? Well, if the RFID chip in the key fob is bad or missing, you'd get these symptoms. Have you replaced the key fob? Did you run the key fob thru the washer by accident? Do you have a second key you can try?

Other than that, I suppose it COULD be the ECM, they RARELY go bad, but if it is not operating right in that it can't interpret the SKREEM data, I suppose that could be it, but ECM failures are just so extremely rare, I just can't imagine that is it.