George, As far as I know they did not open up the iron coffin but they knew it was him because of the inscription on the coffin. I've watched the video several times and it's about 12 minutes long. I too have had trouble in trying to look at the video at times. About the only thing I can think of is if you will provide me with you email address I can put you in contact with the archeologist via his email or I can forward you the site he sent to me. I just don't feel at liberty to give his email address over the internet. My email address has been on this site several times and I don't have a problem with you emailing me so I can get you what you wanted to see. I only copied and pasted his video site that he sent me. He did say he opened up other Confederate coffins but no bones were disturbed. He only wanted to be sure they had not be re-interred in the 1880's. He further stated most of the soldiers were from Mississippi and Texas and Tennessee and perhaps another State I can't recall off hand.
From my understanding and I could be incorrect the archeologist said the burials were from 1862. The 3rd Mississippi Cavalry was not established until 1863 from my understanding. And I can't find a W. H. Partin on the pre war census living in Mississippi that fits a 17 year old. The 3rd Mississippi Infantry however was in that neck of the woods in 1862 but no Partin was located in this unit. It's also plausible the 3rd Mississippi Cavalry had a previous designation or came from different units to form the 3rd Mississippi Infantry.
The unknown Confederate cemetery was located in downtown Hopkinsville, Kentucky by him. I believe since its on the internet I can say the name of the archeologist. It is William F. Meacham and he can be found on Wikipedia. Currently he is listed with the University of Hong Kong. The city of Hopkinsville even gave him the use heavy equipment to dig the site which I found as a little unusual and it's all on the video.