I have no idea, but I think those are 2 terms that technically describe the same material. As you probably already know 12k means there is 12 000 fibers in a single tow and TeXtreme is more about how material is woven to spread load (impact in this case?). On their website they also said that they can also make material from other fibers not only carbon (source:
http://www.textreme.com/technology/what-is-spread-tow-technology/).
PS: Sry for being nitpicky hard headed engineer.
Also if someone wants to buy "TeXtreme", they sell it:
https://primson-composites.pl/tkaniny/weglowe/klasyczne (on the very bottom) (about 35-40€/m)