Crazy but genuine question: can a muscle shift during surgery? I have NF1 and a plexiformNF by my eye and now I have paralysis

I had a temporal browlift in Dec 2022 but have brow paralysis and mild swelling, which was not an issue before the surgery. I know this is a crazy thought, but I had a EMG/ECV today and the dr said something about the muscle not being there (not sure what he meant but he was referring to the front/side of my left forehead right above the brow). He said there's muscle at the top but not by the brow. MRI from saidJuly2023 "cortical thickening left pterion bone". Thoughts? Thanks!!!