Is the wedding in Sword of Destiny the same event as the one Ciri describes to Galahad in The Lady of The Lake? If so, why does she describe it to him? He was at the wedding as well.
Sword of Destiny
The Galahad in Sword of Destiny appears only in the end, during Geralt and Yennefer´s wedding. He helped Ciri to kill a monster (probably Cinerea). He fell in love with her and accompanied her at the wedding celebration. However he seemed to be from different world as he was speaking about Avalon and the Fisher King, which both appear in The Lady of the Lake.
The Lady of the Lake
Here, Galahad finds Ciri bathing in a lake and starts to call her The Lady of the Lake. She tells him about Geralt and Yennefer´s wedding and about the guests including Milva, Cöen... which are that time already dead. At the end Galahad asks Ciri to go with him to Camelot and meet King Arthur.