That is school specific.
In general, though, at schools where the "multiple mini interview" is the only interview, your interview score will only be based on the rubric of the MMI stations. I would think for MMIs, all the observers/interviewers will not review all applicants' files. That would both bottleneck the process, and negate one of the points of the standardized MMI - avoiding biases.
Later, this standardized interview score is combined with the rest of your application in a "holistic review" by the admissions committee at large. Usually, this involves an initial review by 1-3 individuals who would only bring up your file at admissions committee meetings if there is disagreement or an "on the edge" case to be resolved.