Smart Key Fail error

Hi guys
My Cherokee Longitude (2016) karked out today.
Door opened fine, but when pressing the Start button, there was no response.
A recall part message on dash relating to steering lock, but that went away.
Then I also get a 'Smart Key Fail' error that seems to be more persistent.
So...steering locked, handbrake on and cannot start the Jeep.

1. Had roadside replace the battery - no change
2. Tried 2xclick to start remotely - no go
3. Tried pressing keyfob against push start button - no go
4. Another spare keyfob doesn't work either
5. Car will lock/unlock. Flashers work. Rear lift will open/close. Emergency flashers will work

Car now towed into Jeep dealer service centre and they tell me that it will be TWO weeks before they can even LOOK at the car. Geez!

Trying to find out what the problem could be and if anyone else has had this issue

Thanks in advance
Clive