Transfered my save files (23.4) to the new version (24) after last time saving it the first time I went inside the Monolith cave, the one after giving the Blood stone. I give the Blood stone with Roman, Valdemar, and Marcus. They all disappeared because of the Monolith gate cutscene but only Marcus truly disappeared. The others just go back to their previous location. I tried to find Marcus from the map point there's no one here.
Edit: I tried to reload the save file from before i give the Blood stone and dismiss all of my party member, checked that both before and after I give the Blood stone if Marcus was there and he did. At least now I can continue playing peacefully.