Question USD loading mesh but missing textures

I'm having trouble getting my usdc file to open correctly. The mesh loads fine but the textures are missing from the materials.

Here is what I'm using to load at runtime (if there's a better way let me know):

Code (CSharp):

1.                 InitUsd.Initialize();
2.                 var sc = Scene.Open(FullFilename);
3.                 Debug.Log("Opening usdc: " + FullFilename);
4.                 if (sc != null)
5.                 {
6.                     this.Model = ImportHelpers.ImportSceneAsGameObject(sc, Selection.activeGameObject);
7.                     sc.Close();
8.                 } else
9.                 {
10.                     Debug.LogError("Could not find usdc file!");
11.                 }

Which is loading this:


But results in this:


I think it has something to do with the material import settings- I'd like to use a USD Lit Shader if possible, but I feel like even so it should at least load the textures.

 

That works to make the material URP but the textures still aren't assigning- at least not all of them. Looks like Normal and Metallic are but Albedo isn't. Also it looks like it's copying the textures to the project (in the Assets folder) as the game is running? I don't want it to work this way since I want these to load at runtime from another location locally or from a URL. Is there another, better way to import besides ImportHelpers? Thanks!