Everything is the same except of this: Geralt goes to save Jaskier is not in the prison - or Oxenfurt if that matters - anymore.
Geralt wants to find him, spends every little minute he can trying to find out what happened to his friend but he can't wait anymore, not well Yennefer has taken his Child Surprise to do Melitele knows what.
So, with his heart broken and worried, Geralt travels until he finds them again and what happens next it's what happens in the canon.
Ciri is safely at Kaer Morhen with Yennefer when Geralt decides to leave to find Jaskier.
It's still not safe to travel with her and Yennefer is still recovering after her powers are back but she's able to open a portal to Oxenfurt again (yeah, even if Geralt hates portals, it's the safest and easy way to search for his bard).
There, Geralt asks everyone, in every tavern, every littl shop of lutes, he asks even on Jaskier's university, everywhere he could think of to find out what happened to Julian.
After a few hours, Geralt finally discovers that Jaskier was released from the prison a few days back just to be taken away from a group of unknown soldiers and Geralt understands immediately that Jaskier was kidnapped because of him.
And while he's panicking trying to breath and think of what to do next, someone almost rapid as him knocks him off on the ground.
When Geralt wakes up, the only thing he can hear from his cell, it's a voice a few rooms above from where he is, screaming all his lungs out in a heartbreaking pain: Jaskier is being tortured.