I'd sign up for this without a second's hesitation. I actually had the thought of "how could I volunteer?" while reading the article. My personal primum mobile is learning - I'm curious (to some extent) about (nearly) everything - and along with that goes an urge to help satisfy other people's curiosity.

I'm curious about my death, too! I've sat with people who are very close to that edge, and I realize it's the last experience I'll ever have, the last lesson I'll ever learn, and find it poignant that I won't be able to tell anyone else about it. Being part of an experiment like this would be... satisfying, somehow. It feels like it would give meaning to my death.

I respect that you have a different point of view, but I hope that helps you understand what would motivate someone to do something like this.