cant find any scale diatonic option anywhere..
Okay, obviously the Tyro 2 VH is considerably different from the Tyros 4/5 VH2. There still might be hope finding "scale diatonic" within the Chordal "Value" list.
From your second photo example, highlight "Chordal" in the Parameter column. Now scroll up and down the "Value" list where "DuetAb" would be highlighted. Go up and down that option list and see if "scale diatonic" or perhaps a similar name is found there. If so, try singing into your mic without touching any note keys and see if you are getting any VH to your voice.
If that parameter isn't there, then maybe it was an added feature to the Tyros 4/5 VH2. Sorry I can't help further if this is the case. My first Tyros was the Tyros 3, so I am not familiar with the Tyros 2 model.