And he that told the tale in older times
Says that Sir Gareth wedded Lyonors,
But he, that told it later, says Lynette.Alfred, Lord Tennyson, Gareth and Lynette
Your Pendragon Will Vary is an explicit reminder in King Arthur Pendragon. Everyone’s campaigns are going to be different; they’ll pull from different sources (which have wildly different details and tones), emphasize different aspects, and even interpret and tweak rules differently. This is not a mistake, but part of participating in the Arthurian canon.
The same applies to The Death of Arthur.