The captain is always and ultimately responsible.
(As is the captain of an aircraft. There is still debate about the events leading up to the plane crash that cost Leigh-Mallory and the crew their lives in 1944. The question is why was the plane where it was and the suggestion is that the captain (a squadron-leader) felt "disinclined" to argue with an Air Chief Marshal!)
Turney of course would be unaware of this particular universal rule and from what I have seen of him over the last few days would almost certainly have assumed that it didn't apply to him even if he did know about it.
The captain of the Akademik Shokalskiy was in a very difficult position — Catch-22, you might say. Having informed Turney that it was time to go unless he wanted to spend the next goodness-knows-how-many days trapped in the long-since-melted-and-therefore-non-existent sea ice he either upped anchor and left the team behind in which case he would certainly have faced charges in a court (probably Russian unless we can be sure who had jurisdiction of that particular bit of ice floe (!)) of endangering life or possibly manslaughter or (as he did) waited for them to return laying himself open to charges in a maritime court of endangering his ship and crew.
The correct procedure (or so I am told) would have been to tell Turney that he had ten minutes to get his people back on board or he would send a squad, properly armed, to force them back on board, with or without their equipment. Turney would have had a conniption fit, as would all the other greenies, but any subsequent attempt to bring charges against the Master of the vessel would have failed. For the reasons given above.
Incidentally am I the only one who thinks that what was actually on board that ship was a group that could best be described as Australian Hooray Henries? They certainly come across to me as that sort. Few brains; massive sense of entitlement; lots of money (probably daddy's). Led by one of the preening egotists that turn out to be the villain in episodes of Morse!

geronimo
I think I'd need to do some research on that.
The law of the sea is clear that the Master is just that and everyone on board is subject to his diktat. I don't think there is any provision for him to abdicate that responsibility under any circumstances.
Turney may be in charge of the expedition and in days past there would certainly have been ships dedicated to Arctic/Antarctic exploration and research but as we saw with the Aurora Australis, ships will respond to an emergency call ahead of anything leaving several researchers fuming because she upped and left with half their equipment still on board.
The logic is simple, especially in extreme parts of the world. If you jeopardise your transport then there is a fair chance none of us is going to get home. Do as I say!
In the situation that the Akademik Shokalskiy was in it was (or should have been) the captain's decision to get his passengers off and retain a skeleton crew sufficient to get her back into open water when and if the time came.
But then none of this was an Antarctic expedition, was it? And Turney is certainly no Mawson or Scott! This was a PR jolly so goodness knows what rules would apply!