Re: why don't the eyes line up on the Salvator Mundi?
Hehehe yeah, might have been that. Or the eyes didn't line up on the model. That happened to me quite often when I was doing street portraits. People's eyes didn't line up or their faces were weirdly distorted, I'd get it accurate and they loved it. Thought it was flattering the more wrinkles and facial flaws I put in, but that's the likeness. Also wrinkling is naturally simplified in pastel and people look their best in good lighting while having a good time, rather than their memory of how they look under garish bathroom lighting when they're puffy, sallow with bed wrinkles on cheeks, bags under eyes and bedhead. No matter how accurate I got, people took them as flattering.
So I don't doubt eccentricity like eyes lining up. In a historical painting I honestly suspect "the model" because they were all very concerned about getting the likeness.
From what I read on one of the articles, Salvador Mundi was a cartoon Leonardo did and a lot of his students painted versions of it. Which makes sense that it was a lesson among other things. Whether he painted the really pricy one or not, eh, not my problem.