A man fondled his wife during his qadha fast, and ejaculated. As he did not intend this to happen, he wants to know what he should do?

If he was certain that such foreplay would not arouse him, certain that he could not reasonably expect to become excited by his or his wife’s actions, that there was no reason for him to ejaculate, but he then did, his fasting is valid. However, if there was a strong likelihood that his foreplay would bring about his ejaculation, then his fasting is not valid. That would mean that the qadha could not be counted.