1. Download the Licensee repro and open (link in comments).
2. Observe the trees, and the random bend in them.
3. Open the material /Content/BFGame/MaterialLibrary/MaterialV2/M_V2MasterOpaque
4. Delete the PerInstanceCustomData expression and hit "Apply".
5. Observe that all the trees in the level stand straight.
6. Open the Material Layer /Content/BFGame/MaterialLibrary/MaterialV2/Layers/ML_VertexBend. Observe it uses PerInstanceCustomData to calculate the bend, but only gets the data correctly when the base material has a PerInstanceCustomData expression.