Issue with Ninjaripper and Sketchfab

I’m running into some issues attempting to rip models from sketchfab using ninjaripper. It was working to a reasonable degree a month or two ago, but now ripped geometry seems to be flattened against a cube. Example:

Reading some threads on sketchfab, it seems like the developers were aware of ninjaripper and other ripping programs and were taking measures to make ripping more difficult.