As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CAPT O2 MASK PRESS TO TEST BUTTON IS BROKEN AND CANNOT TEST O2 MASK. SWAPPED CAPTS WITH 4TH OBS, FWD TO MEL/PLAC 25-11-07, "M" PROC C /W. R & R ADDITIONAL OBSERVERS (FOURTH OCCUPANT) OXYGEN MASK STOWAGE BOX IAW AMM 35-12. OPS CHECK GOOD AND NO LEAKS NOTED. M.E.L AND PLACARDS REMOVED. "M" PROCEDURE REVERSED. (LP: 8675982). AIRCRAFT WAS GROUNDED