A question about Alcatraz?

The three prisoners who escaped from the prison in 1962 were never to be seen, nor heard from again. Do you think they really made it to shore alive? While it is certainly plausible, and a possibility, I personally think it's highly unlikely that they even got close to making it to shore judging from the fact that they were never to be seen, or heard from again. The bodies were never found, meaning in my opinion it could be that they suffered from hypothermia, and drowned and the bodies sunk so deep underwater the cops couldn't find them. Or they could have got eaten by the sharks while underwater trying to make it ashore. We will never know whether or not those three criminals were able to make it to shore, Frank Morris being among the three who escaped.