I Think Me And A Friend Glitched A Dungeon... Any Ideas How To Fix?

We're doing Galleon's, with me and a friend in a party, and as we defeated the ship battle, we had to do the boat parkour and enter to do the treasure vaults. Naturally, I finished and entered the room, my friend on the hand missed a jump, no big deal. But, as I entered, all the boats required to reach the other side, completely despawned, and now he's stuck on the other side.

It seems other dungeons have similar issues with party play, like the entrances always closing once one of the two enter.

Any ideas on what to do?

 

Idk but it you think this is a bug, report it to the bug section of the forums.