Navmesh for differently sized pawns; how?

So, can anybody explain how to set up navmeshes for differently sized pawns? I set up two navmeshes for two actor types, and google led me to answerhub thread that claims that this is all I need to do, and the UE will then assign pawns to navmesh best suited for their size automatically. Yet this doesn’t happen.

Clearance of these crawlspaces is 1 meter high, the pawn’s collision capsule is only 60 centimeters high, but the pawns still refuse to go under, keeping using the green navmesh intended for bigger actors.