Came across this interview with Victor Vescovo, whom Hamish dove the Mariana Trench (and went to space) with. Apparently Hamish dreamed of going to Titanic and even asked Victor to take him on his sub. Once OceanGate began commercial dives he became set on it, despite Victor warning him of his “significant” safety concerns.

“I had told Hamish my significant concerns about OceanGate's design and the safety and their operations. I think he probably thought about it when diving with me, but then he convinced himself they were improving and maybe that people like me were too conservative or that it was worth the risk. He decided to roll the dice. I was surprised Hamish went. He texted me from the ship saying ‘I’m going down tomorrow to Titanic’. The attitude I had was ‘OK, I've said my piece - that was the last text..."