the first quote may means about dali or branbal, cause of Zidane which may be detect by kuja, or probably the place zidane was borned.
the second quote may means about Vivi and his black mage family which affect the story when Vivi is caught.
the third quote may means kuja plan of destroying alexandria, lindblum and burmecia, the useless beasty might means Queen Brahne.
the last quote is kuja on silver dragon which seen the act of the party at dali, it only end after kuja's defeated.

I think it related to vivi, zidane and kuja
Or is quote then it is: 'How do you that you exist, maybe we don't exist'
Just mumbling, forget it.