Wouldn’t gastric sleeves be pretty quickly identified as being a medical device? Find a few in coffins and the theory pops right out. The beauty of the Roman 12gon is that it’s ubiquitous, complicated, but not documented and not clear even what category of things they were used for. Like a rubix cube.

She thought it was the purrfect crime.

Paint a stripe or two on your crossbar with distinctive colors. Easy to do, easy to notice & document, hard to duplicate, and hard to remove.