I was just wondering.
How exactly Emhyr justified and proofed to the rest of Nilfgaard that this Ciri is the real Ciri and on top of that that she is his daughter?
Doesn't make seance for me. Can anyone share their thoughts?
He kills anyone who would oppose him, and the rest support him, and want to marry one of their sons to Ciri to obtain the throne. In the endings where Emhy survives he basically completely eliminates any opposition to him whatsoever. He can do whatever he wants.
The other nobles are all angling to have Ciri take one of their sons for a husband, as Voorhis mentions. That's pretty much the only reason there isn't a total rebellion against a Nordling taking the throne. We know via book canon that Voohis gets the throne either way, either ascending after Emhyr gets shanked, or marrying Ciri.