Isn't it possible that the inscription witnessed by D'Antraigues and many others could have been taken to similarly 'offensive'? I don't have a ready image to post but the original images appear here in this PDF. I have a hard time believing that D'Antraigues necessarily made up this witness given the fact that we other testimonials to the existence of the same object.
dating back to conversations with his grandfather, Gaston Frank. "He said we represent one of the last descendants of the Frankist Jewish faith in the world," he muses. "I grew up thinking that our family was something like the Last of the Mohicans."