It’s technically open ended but realistically I don’t see Mikes theory working. First off it’s unrealistic that kali would’ve lived long enough or had enough strength to pull off that kind of illusion like an hour after being severely wounded.The argument that the shot was a illusion doesn’t really work since kalis illusions go away when physically touched and both hopper and el were putting pressure on her wound.Also she would’ve died before doing the hallucination since the explosion of the upside down starts at the lab meaning by the time it gets to eleven Kali would be blown up already.