I don't have much insight into these emissions tests, but I do know that I had to do at least three 30 minute drives after clearing codes for everything to show ready.
Some other things to consider:
- Are you sure you're back to stock? I know HPT's comparison function doesn't really show when you change diagnostic codes. Or if you flashed your original read, are you sure the original read was stock?
- You mention no codes in the ECM, but what about other modules?
- You could try disabling the tests, maybe they'll show ready by default or not available and that will be good enough?