UOctreeDynamicMeshComponent will not render because SceneProxy is always null

Development Programming & Scripting C++
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Not sure if I’m just doing something wrong here, but on Windows, in Unreal Engine 5.4, if I attempt to make any changes to my mesh, UOctreeDynamicMeshComponent::NotifyMeshUpdated will early return, because the UOctreeDynamicMeshComponent::GetCurrentSceneProxy check always fails.

I’ve set some breakpoints to confirm that UOctreeDynamicMeshComponent::CreateSceneProxy was called. It seems as if the address is changing from the point it is created and the point GetCurrentSceneProxy is called.

I thought there may have been a problem with the UPrimitiveComponent::SceneProxy assignment after CreateSceneProxy was called, so I tried retrieving it from SceneData::GetSceneProxy in NotifyMeshUpdated. A pointer exists at that point, but the cast to FOctreeDynamicMeshSceneProxy* seems to fail.

I’m editing the mesh through EditMesh, which calls NotifyMeshUpdated itself. I’ve tried a handful of things, such as moving the logic to Tick, and marking the render state as dirty every frame, just to see if I can get it to work in any way, to no luck.

My minimal reproduction is:

OctreeDynamicMeshComponent->GetDynamicMesh()->EditMesh(
	[](FDynamicMesh3& MeshToChange)
	{
		MeshToChange.Clear();
		int Vertex0 = MeshToChange.AppendVertex(*new FVector3d(0.0, 0.0, 0.0));
		int Vertex1 = MeshToChange.AppendVertex(*new FVector3d(100.0, 0.0, 0.0));
		int Vertex2 = MeshToChange.AppendVertex(*new FVector3d(0.0, 100.0, 0.0));

		int Triangle = MeshToChange.AppendTriangle(Vertex0, Vertex1, Vertex2);

		if (Triangle > -1)
		{
			UE_LOG(LogTemp, Display, TEXT("Valid Triangle created"));
		}
		UE::Geometry::FMeshNormals::QuickComputeVertexNormals(MeshToChange);
	},
	EDynamicMeshChangeType::GeneralEdit
	);
OctreeDynamicMeshComponent->MarkRenderStateDirty();

if (Material)
	OctreeDynamicMeshComponent->SetMaterial(0, Material);

I’ve tried looking around to see if I’m maybe just misusing it, but the only thing I’ve come across is a post from 2022 where someone was running into a similar problem as me, where the SceneProxy was always null: How do you use a UOctreeDynamicMeshComponent?