The Greek text can be seen in this image:
Here's a better view of the text:
Well, of course, Square had put random Greek alphabets on certain walls in the game just to make things more interesting. Of course, they don't make sense as a whole. I believe that the developers used some translation (from japanese -> greek) that's why they don't make sense.
After researching for a while trying to find out what was Square really meant to say.
The only closest thing I've found so far is the 'daughters' word. Just that word, nothing else.
Google translation shows:
daughters -> κόρες
The bold word above look relatively smiliar to the one in the picture. I'm not so sure about the following word after κόρε. I'm still trying to find out.
But, I'm pretty sure that Square was meant to say something about daughters somehow.
Ok, let's see...
All of the witches are women in VIII and they are powerful. They are daughters of someone, then? Perhaps, Hyne?