Is Kaffara still obligatory on a man who was masturbating while fasting, and while not intending to reach ejaculation, did accidentally trigger climax which led to ejaculation and caused his fast to be broken?
If he knows that his masturbating can lead him to ejaculation by accident, his act of masturbation is a sinful act and he has to pay Kaffara along with Qadha of the fast if that day.
If ejaculation happens completely unintentionally then no Kaffara.
Wassalam.