Nolan Wells Death: Video Shows Friend Group on Boat Dock Before Horn Island Trip

Nolan Wells' self-described best friend is sharing footage of a large group of young people gathering on his boat dock, preparing for their fateful trip to Horn Island ... the morning before Nolan vanished.

Nolan's friend, Warren Hudson, invited YouTuber Brandon Tatum over to his Mississippi house ... where Nolan allegedly boarded a boat and headed out to Horn Island on the Fourth of July.

Tatum pans the camera around the dock ... and later shows surveillance footage from the morning of July 4 ... showing nearly two dozen folks milling around three boats, preparing to head out to the island.

Nolan is not specifically pointed out in the video, but Tatum says he was amongst the group of young folks who boarded the three boats.

What's interesting ... none of the boats in the surveillance video matches the boat that we seemingly saw Nolan hanging out on in footage from Horn Island.

The boats in the surveillance footage are different and smaller than the boat from our Horn Island video, which is believed to be the final image of Nolan alive.

Warren and Tatum also ventured back to Horn Island, returning to the place where they anchored on the Fourth of July ... near where his body washed up two days later.

Nolan's friend claims he decided to hang back on the island with a girl when Warren and the group left in their boat around 4:30 PM.

As you know, investigators are still digging for answers about what happened to the teen. His body was found in the shallow water just off the island on July 6, where currents are known to be hazardous.

Nolan's family commissioned an independent autopsy, which found he may have suffered an injury to the back of his head ... though that's just a preliminary finding.