Hi Bill,
Very interesting exercise, thanks for posting it.
I agree the surgeon can't see.
Both the young man's eyelids are drooped (sleepy) and he has a distinctly different nose with a bump on it. As well as your observations.
I'd go so far as to say that the one looks vaguely French (or Continental at least), while the other looks like he is of Irish origins.
If they had wanted to do an unbiased authentication, why did they identify the subject? Could it be worth more money if it is of Lincoln?