I would not wish death by drowning on anyone, any more than I would wish them death by bludgeoning about the head and neck while still a youth.
I have never heard of the Sea Shepherd before, and I may think the crew's words are overly harsh and insensitive at this time ... and yet, I must admit that I feel glee to hear that someone is giving voice to the opinions that social propriety would prevent me from verbalizing.
(I'm most fond of the phrase "cigarette-smoking ape with a club")
Seems that karma can be a bitch to people who make their living literally going out of their way to crack open other creatures' skulls. May the victims of the sunken boat and their victims rest in peace.