Tim,

I'm inclined to say "no". A plug door has to travel laterally to unplug.
The door supports on the bottom of this car door do not seem to allow for
this. Note also that the vertical rod does not go all the way to the bottom
to a track-riding lever arm, so it could not unplug the bottom of the door.

I've seen pictures of a PRR wooden car with a similar arrangement. If I can
recall where, I will investigate to see if that car could have been plug
door or did it too fail the test at the bottom.

regards,

Andy Miller