Where there's smoke there's fire... (well hopefully not in your case)
If it looks like a duck and quacks like... it probably is a duck.
Plain and simple... You have a diesel leak.
Best job rather than just "looking" in the engine area, is to physically touch all areas related to fuel
, paying particular attention to touch underneath the fuel
fittings and hoses as whilst the fuel may not be dripping, it can still be there and smell accordingly. Fuel can run along the underside of hoses out of sight but still smell.