DC Young Fly's partner Jacky Oh! died from cosmetic surgery complications, but the doctor who operated on her won't be charged with any crimes ... TMZ has learned. The Miami Police Department tells TMZ ... the medical examiner ruled Jacky's death accidental, and homicide detectives will not launch a criminal investigation. As we reported ... Jacky flew to Miami back in May for cosmetic procedures, and she was prescribed medications after the procedure. Jacky then got a headache, went back to the surgeon for a post-operative appointment, decided to get a massage to alleviate her pain and was advised to swap some of the pills she was taking. According to the ME report, Jacky then began to feel her head "burning" and she had difficulty speaking. A family member called 911 but Jacky was unresponsive before first responders arrived, and she was ultimately pronounced dead at a hospital. The autopsy report noted Jacky had swelling in her brain and extensive bleeding of the skin around her torso. In a since-deleted social media post before her death, Jacky said she was in Miami for a "mommy makeover" with Dr. Zachary Okhah. Dr. Okhah released a statement shortly after Jacky's death, though he didn't directly address the situation ... instead saying his office "remains devoted to the highest quality medical care." The doc added ... "All aesthetic procedures are performed in a hygienically safe environment to universally recognized medical standards." There was some question as to whether anyone would be charged in Jacky's death ... but on the heels of the Medical Examiner's findings, cops say that won't happen.