Gone are the days when crankcase pressure is vented to the outside. Now it's routed into the intake.
I wasn't aware of this new blow by routing but makes sense with todays emissions. My C9's vent will choke you out so I have extended electrical grade pvc to dump it way behind the sleeper. So you are saying it is routed back between the air filter and the turbo. I can see where this would be a problem, especially with newbies checking oil level on a not so level parking spot thinking it's way low when it's not.
Your bit about the Detroit 2 stroke emergency shut off got me to googling
Let Me Google That
and found this, interesting it's Caterpillar yellow, yet not made by Cat. Looks like they have several different models;