As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 5188 - AFTER BLEED TRANSFER, NOTED STRONG ODOR FOLLOWED BY SMOKE IN TOILET CAUTION MESSAGE. RETURNED TO LEX, LANDED WITHOUT INCIDENT. FOUND OIL IN WATER SEPARATOR. REMOVED OIL AND CLEANED COALESCER BAGS. INSPECTED PACK FOR LEAKS. NO FURTHER DEFECTS.