i am a real diesel mechanic
lots of opinions here.
not all are bad.
i notice your symptoms list included sheen on the water
was this prior to new injectors or after?
if your oil sump is full, and is not diarrhea looking, then it is diesel.
drain it at once, and congrats, your engine is sparkly clean inside.
i would like a sump fill rate.
change the oil start the engine, top it off to the correct level, run the engine 15 min at idle, allow to sit for 10min, check again
did the level go up a noticeable level? if yes, then its the injection pump.
if no, it may be injectors. injector pumps are cheep to rebuild here in America.
look for rebuild shops, i have seen some as cheep as $400 for a 6 cylinder tractor engine. any good rebuild shop can repair/rebuild any injection pump.