Third fix tried and failed: the terrain staged in the probe map with collision disabled entirely. The pawn
still rises (Z 315 -> 421), exactly as with collision enabled.
With that, the terrain's convex hull, its collision channel and its collision itself are all eliminated, and
the failure survives in a map whose only difference is the presence of a 279 m static mesh.
The player is unaffected throughout - re-checked after every attempt, still standing on Sidewalk_North_07
at 157 cm - so nothing in the walkable demo regressed.
Deferred rather than guessed, per AGENTS.md: the task is marked deferred with the three failed fixes, the
probe workflow and switches a fresh session inherits, and the next question framed precisely - why a map
containing a collisionless 279 m static mesh changes a physics body's behaviour, which points at streaming,
memory layout or the broadphase rather than at collision authoring.
Generated probe levels deleted; the tools stay.