Loved the concept. Very Trolley Dilemma. And also very science experiment vibes (I've participated in a few in-person ones, it's seriously the same vibe, good job on that!). 

I understand the lack of context add onto the experiment vibe (so it would not influence the participant's choice and the experiment as a whole), but I would have wanted a few more different emails (from your family/friend/someone who would be targeted/the other scientist). Or maybe you have to sign the consent form before you sit in front of the button (the one that tells you partly the purpose of the study without telling you the true significance).

While I understand the inclusion of the score page at the end, I think the cliffhanger would have worked better had the number at the bottom not been included. That way it would have fit the theme of this competition a tad more. Sure you don't know what happens to your character, but it would have had a bit more punch if you didn't know what your action had done at the end (did I truly killed those people? was the number of people killed what I was told it would be?). 

UI wise, it was cool to see something different compared to the other game. That button was truly tempting me as soon as I sat down. But the screen was not great to read the emails. The glare and some formatting issues made it hard to read some of the parts, which is a bit of a shame. I could have been neat to have some sort of animation when you pick the option Close you eyes.

Long comment for some more nitpicky things :P

Fun game. Would kill those people again.

Interesting concept! I did feel myself wishing for a bit more context, however - be it through environmental objects or something else. Definitely fun for a quick play through, though!