As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE, FLIGHT CREW NOTICED A MODERATE VIBRATION COMING FROM THE BACK OF THE AIRCRAFT. AFTER FURTHER INVESTIGATION, THE CREW DETERMINED THAT THE VIBRATION WAS COMING FROM THE RT NACELLE. SHORTLY AFTER, THE CREW RECEIVED A RT GEN FAIL CASS MESSAGE AND THE RT GENERATOR DROPPED OFFLINE. CREW DECLARED AN EMERGENCY AND DIVERTED INTO AEX.