Does "Root A" follow the fact about Takatsuki and the One-Eyed Owl?
Yes, it's shown clearly in the anime that 


   Sen Takatsuki is the One-Eyed Owl.


They started giving hints about it in first half of the episodes in Season 2.



Season 2 Episode 1


   Kaneki joins Aogiri and is welcomed by this girl named Eto
 

 Eto seems to like Kaneki
 




Season 2 Episode 2


   Later on in the next episode, Eto removes her bandages and smiles while taking Kaneki's name
 




Season 2 Episode 3


   In the next episode, we see this author Takatsuki and she smiles the same way as Eto while hearing Kaneki's name - Can safely infer that Takatsuki is actually Eto
 




Season 2 Episode 7


   The same smile pattern after hearing Kaneki's story from Hinami. Takatsuki is Eto confirmed!!
 




Season 2 Episode 11


   I think you missed this part. It was shown after the ED theme in Season 2 episode 11. It clearly shows that Takatsuki is the 2nd Owl, and the only daughter of Yoshimura (who is also called non-killing owl)