Your Sketchfab model is OK, but the exported model gives a Sketchfab error and has no texture. Exported model looks OK in meshlab.
I finally figured this out. Unlike other models, it was not possible to upload the zip file.
I had to unzip and upload all the files at once.
Hi rmark, thank you for sharing this and I am glad to see that you were able to resolve the issue. This will be very beneficial for others who may come across the same issue.