Ok, so this is from Hasbro Pulse on their official website:
- Training himself in the ways of the dark side of the Force, Carnor Jax became one of the most formidable members of the Imperial Guard. He betrayed his brotherhood by usurping the Imperial throne.
Ascending to the Imperial Throne is Carnor Jax’s storyline. So, they wrote ad copy for Carnor Jax.
That text is also on the inside flap of the box image:
So, at some point, they definitely intended on making a Carnor Jax figure. They just ended up making Kir Kanos by mistake. Either that or the figure was designed and made to look like Kir Kanos, then the wrong name somehow made it into the copy writer’s inbox and they wrote the copy after researching Carnor Jax’s story.