Identification of Booth's body

[RJNorton]

I am curious about Dr. Merrill's (alleged?) visit to the Montauk. I realize there is no written report in which Dr. Merrill gives an account of his findings. Some sources say Dr. Merrill pried open the corpse’s mouth and positively identified his fillings. What is the original source for this? Who saw Dr. Merrill do this?

What I am asking is whether or not the entire Dr. Merrill story might be apocryphal. OR are there eyewitness statements of people on the Montauk who actually saw Dr. Merrill examining the remains? I suppose it is possible that Merrill did indeed make an examination, but neither Bingham nor Holt took down a written statement by Merrill. But I am curious about any original sources that verify the truthfulness of Merill's visit. Why would Bingham and Holt question others who identified the remains (and these statements are available to us) but skip Merrill completely?