Why is VR crashing with Hierarchical Instanced Static Mesh?

Upon running around in my game world, in an area comprised of many Hierarchical Instanced Static Meshes, I keep getting the same crash. During the FHierarchicalStaticMeshSceneProxy::GetDynamicMeshElements() call,

    // Instanced stereo needs to use the right plane from the right eye when constructing the frustum bounds to cull against.
    // Otherwise we'll cull objects visible in the right eye, but not the left.
    if (Views[0]->IsInstancedStereoPass() && ViewIndex == 0)
    {
    	check(Views.Num() == 2);
    						
    	const FMatrix LeftEyeLocalViewProjForCulling  = GetLocalToWorld() * Views[0]->ViewMatrices.GetViewProjectionMatrix();
    	const FMatrix RightEyeLocalViewProjForCulling = GetLocalToWorld() * Views[1]->ViewMatrices.GetViewProjectionMatrix();
    
    	FConvexVolume LeftEyeBounds, RightEyeBounds;
    	GetViewFrustumBounds(LeftEyeBounds, LeftEyeLocalViewProjForCulling, false);
    	GetViewFrustumBounds(RightEyeBounds, RightEyeLocalViewProjForCulling, false);
    						
    	InstanceParams.ViewFrustumLocal.Planes.Empty(5);
    	InstanceParams.ViewFrustumLocal.Planes.Add(LeftEyeBounds.Planes[0]);
    	InstanceParams.ViewFrustumLocal.Planes.Add(RightEyeBounds.Planes[1]);
    	InstanceParams.ViewFrustumLocal.Planes.Add(LeftEyeBounds.Planes[2]);
    	InstanceParams.ViewFrustumLocal.Planes.Add(LeftEyeBounds.Planes[3]);
    	InstanceParams.ViewFrustumLocal.Planes.Add(LeftEyeBounds.Planes[4]);
    	InstanceParams.ViewFrustumLocal.Init();
   }

Specifically at this line

InstanceParams.ViewFrustumLocal.Planes.Add(LeftEyeBounds.Planes[0]);

I get the following assert Array index out of bounds: 0 from an array of size 0

Any idea what is going on?