Any chance you could have sat on the key? 
That was my initial thought - but when I tried this later, I can't make my doors open from in the house!
The more I search and read, the more its looking like I'll have to go back to VW as its a proper fault.
I can hopefully get my whistling window seals changed at the same time though!
Had a brief look outside today - and they're still up thankfully!