From the blog article:
To get you started on your winter adventures, we present four reward cars (three new to Horizon) during the four entirely wintry weeks of Horizon Holidays Mix-up, all with four doors and room for a ton of presents.
Have I missed something, which of these can be considered as not new to Horizon?
The article also mentioned initially (don't know if it was changed since) that the CTS-V was perfect for the city with a 2-litre turbocharged engine. I suspect they swapped a car last minute like they did with the Hot Wheels expansion, and not every reference in the article was caught.
As for cars with four doors, a 2.0 turbo, and that have appeared in Horizon previously, maybe the 2013 Focus ST was the one? Who knows.