Two months later I crossed a guy on the Steam forums that implied that this has been fixed and that now letting Gale die and resting for few days without saving him leads to a game over.
I'm not sure if he put the theory to the test or if he just took the game's narration for granted.
I'm here to ask confirmation, since I haven't completed a new playthrough since Patch 3 released: did anyone test if they actually fix this?
Yup, the cinematic itself is not done yet ("Cinematic pending"), but you die after sleeping 3 times after Gale's death.