Not a linux user (yet) but I assume if you click "Open save directory" in the save menu it'll send you there?
Yep, this should work and open the correct directory. For me, as an example, using Lutris with a Proton Wine version, the directory is: ~/Games/umu/umu-default/drive_c/users/steamuser/AppData/Local/VotV/Saved/SaveGames/
Can't believe I missed that button lmao
Thank you!!