Does Orochi know Haise Sasaki? Orochi reacted when he saw Haise Sasaki (Tokyo Ghoul :Re episode 1) and said 


  Hmmm? There's something about him...


leading me to believe that he recognized Haise Sasaki from somewhere before. How did Orochi recognize Haise? Are they anyhow related from the past?
You will get your answer in the anime Tokyo ghoul :re (episode 2)



Dialogs from Orochi 


   No matter how far you go, you're always irredeemable, huh... Kaneki?


Haise replies 


   Nishio.... Senpai.. ? (Haise loses control here since he starts getting flashbacks from his lost memories)