Schrodinger's zombie?

Hello! I was fighting with some zombies and now i can't get out of this basement. This fat zombie only appears for a fraction of time when i try to walk to the ramp. I tried so shot at its direction, but I don't know if i can deal damage to it in my position. Someone know how i can get out?

Hello! I was fighting with some zombies and now i can't get out of this basement. This fat zombie only appears for a fraction of time when i try to walk to the ramp. I tried so shot at its direction, but I don't know if i can deal damage to it in my position. Someone know how i can get out?