Maybe the oil is dripping down from higher up, i.e. a camshaft seal, and running down?

Are you losing so much you can't drive anywhere? If not, you might test the ventilation system before replacing any seals. You can open the oil filler cap with engine idling. At idle, the cap or a flat sheet of stiff plastic, etc. will rest on the opening if the system is drawing proper vacuum. If the cap or whatever wants to jump up, there is overpressure. You might also see oil coming out of the dipstick. If system is clogged, you may need to clean all of the tubings, possibly including the oil separator, not just the flame trap.