As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTS OIL QTY DROPPED TO ZERO THEN CAME BACK TO 1.5 TO 2.0 FLUX, CURRENTLY READING 18.0 CREW ELECTED TO RETURN TO DEN, MX TO MEET AND DEBRIEF CREW VERIFIED ENG 1 OIL QTY FULL. NO LEAKS. APPLIED MEL. VERIFIED ENG 1 OIL QTY FULL. NO LEAKS. APPLIED MEL. TOMC APPROVES MEL 7931A THIS IS #1 ENGINE OIL QTY