Seems to me that the photo they show looks more like Darth Vader than Judge Jeffries.
Nothing to compere with to see what might have been being photographed.
I'm also not sure why Mary Anning would be wandering round a museum missing a head when she died of breast cancer.
Radical surgery gone wrong?
It does seem a bit odd to jump to the conclusion that a ghost must be someone famous.
Somewhat reminiscent of past-life regression people being more likely to end up channeling past royalty than a dung-encrusted peasant.