As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PRIMARY STAB TRIM RUNAWAY INITIALLY UNCONTROLLABLE, ACFT PITCHED DOWN LOSING 2000 FEET UNTIL ACTUATING RED DISCONNECT BUTTON & TURNING ON SECONDARY TRIM, INDICATION WE HAD WAS ERRATIC FROM DASHED YELLOW LINES TO FULL UP & DOWN INDICATIONS. WE HAD CYAN AUTO PILOT A & B FAIL. SECONDARY TRIM OPERATIONS WERE NORMAL.