thanks for the update, do you know which custom assets it could be from the model, I could try removing these when I do tests on 3.4 later today hopefully. I am on a project so if I can find the time to do this I will but it might have to wait
Unfortunately the human readable asset names don't show in the renderer, just their unique identifier (e.g. 23139ce0-a45a-4d9c-90f7-b586b0df598c). As mentioned above, I'd recommend to hide all assets for testing.
Also in case the image shows up completely dark as in the screenshot above, it'd be interesting to know if that changes if you disable hardware ray-tracing in the renderer settings.