I can only say this from what some of the chinese people in my parents' lab have said.
Many went to top medical school or top college back in China and then came here on visa to do grad school or to follow a spouse here. I know the few that managed to practice in the US spent YEARS prepping for the step 1 and 2 of the boards b/c they have to relearn everything in English. Now, most of these people are fairly fluent in English and lived in the US, but the language barrier for medicine was still immense. But then even if they finished the boards and got decent scores, they still have no guarantee of a residency as they are not US medical school graduates....so many just wait after they get their scores and hope a program will take them.
I know of no Chinese person who was accepted into medical school straight from China, but I have limited experience with foreign graduates.
If your friend really wants to go to med school here, the only way I can think of (short of finding a cure for cancer) would be come here for graduate school (which they will pay), get a job, work until you qualify for green card or citizenship or marry an American and get citizenship and apply to medical school.
Otherwise, she would need to go to med school in China---although if she's not already in med school as an undergraduate, I don't know how the Chinese school system will work in her case---and then come here for grad school and then try for the boards.