It seems that some of us are from worlds that are far more technologically advanced, which means our knowledge of medicine surpasses that of the doctors here.

Dr. Grey is likely far more qualified than some of the rig doctors.

Also...there are significant chances the rig doctors may be more...exploitative in nature. During my exam, they seemed uncomfortably fascinated with my physiological differences.

I wouldn't put it past them to take advantage of any times we need treatment to engage in unnecessary experimentation, especially for those of us that aren't human.