(For a moment there I had to stop and re-read whether I am talking about Sapkowski's Witcher or my life)
Can't be more perfectly said than that, hahaha
And death, and what happens after it, is an unconfirmed rumor until we experience it ourselves. Who's to say that Sapko did not intend to imply that destiny exists as an entity in the witcherverse, as you said so yourself, even beyond "death" in the end of the sagas?
The more you think about the damn series, the better it gets.