Geralt of Rivia

Bump on this. Anyone figured out anything?

Hi everyone, Not sure if I missed it, or it disappeared from my inventory. I killed the legendary gunslinger, E. Granger and somehow, I may not have picked his gun. But I am pretty keen on details, and the rare gun icon on mini-map would be easily noticed. A similar thing happened when my Schofield revolver that I got from Valentine doctor, went missing on my inventory. But that's for another story. Anyway, I am too far ahead in game and realized that it is not in my inventory. Is there a way to get it back?