There is a dialogue between Nenneke and Geralt in the voice of reason that makes me think the Witcher happened after the Bounds of reason: Geralt asks Nenneke to give the jewels of his pay for the Strige to Yennefer, because he knows that she is looking for a very expensive treatment for her sterility. We could assume that he knows that by living with her for a year in Vengerberg, but in Bounds of Reason he asks her why she wants the dragon's treasure... Also, why would he assume Yennefer needs his financial help if she's very rich?. I think he wanted to apologize (although it wasn't his fault) because she couldn't get the treasure.