As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT 08:57 Z FLIGHT LEVEL 29,700, NR 4 ENGINE COMPRESSOR STALLED EGT WENT TO 908 DEGREES CELSIUS AND ALL OTHER PARAMATERS REMAINED NORMAL. SHUT DOWN NR 4 ENGINE I/A/W POLAR PROCEDURE. FOUND METAL IN TAIL PIPE. ENGINE REPLACED PER POLAR AIR CARGO FORM M7100-002.