I did say:

I haven't yet worked out a good way to draw the line in the escalation scenario, since I suspect that "whatever level of discomfort I, personally, wouldn't voluntarily experience to save some random person from 50 years of torture" is unlikely to be the right answer.

The scenario you present is among those I have no suitable answer for for this reason. However, I lean towards preferring the 50 years of torture for 1 person over 49 years for 100.