In the problem statement, an actor has control over whether this 1 person or those 5 people die. If they choose red, then 1. If they choose blue, then 5. (Failing to make a choice is choosing blue.) If after playing the scenario, they knew someone would use a Men In Black pen on them to completely forget what happened, is there a rational argument against choosing red?
(I realize this might read like trolling, but I genuinely don't find the original problem a difficult one if you eliminate the human guilt aspect.)
Actively choosing an action to deliberately kill someone else could be weighed negatively by the machine, it would depend on the programmer.
I don't think you can apply the word "rational" here, if you don't take a position of utilitarianism, not deliberately killing the person could be axiomatically rational. It's not just about guilt.