McDonald's Old Car Advert - what's with the registration?

Have you seen the recent McDonald's advert where a mum gives her son her old car as a birthday present?

Yet what's with the registration - KO08 UBZ?

A search on the government website indicates that this registration applies to a grey Ford Mondeo. And this car is neither grey nor a Ford Mondeo.

See photos below.

So what's going on here?

Either someone else's car registration has been applied to the car in the advert (is that legal?) or the information on the government website is incorrect.

Answers on a postcard please.