To be fair, USFCOM's dean places a massive importance on the MCAT. So, doing well in their master's program doesn't necessarily help you if you don't have a great score (lets say 512+). But there are a lot of students who do well in the program and are accepted if the only thing holding them back was ugpa. I believe 8 students were accepted to USFCOM from the master's program and their avg stats were 3.4 ugpa, 3.84 grad gpa, and 514 mcat. You don't take classes with med students so the competition is lower, but doing well shows that you are willing to work hard and a good mcat score shows your caliber.
Tldr...the masters will help someone who has a bad gpa and good mcat, won't help someone get guaranteed acceptance to a med school.